group_theory.index ⟷ Mathlib.GroupTheory.Index

mathlib commit https://github.com/leanprover-community/mathlib/commit/65a1391a0106c9204fe45bc73a039f056558cb83

@@ -76,7 +76,7 @@ theorem index_comap_of_surjective {G' : Type _} [Group G'] {f : G' →* G}
     simp only [QuotientGroup.leftRel_apply]
     exact fun x y => iff_of_eq (congr_arg (· ∈ H) (by rw [f.map_mul, f.map_inv]))
   refine' Cardinal.toNat_congr (Equiv.ofBijective (Quotient.map' f fun x y => (key x y).mp) ⟨_, _⟩)
-  · simp_rw [← Quotient.eq''] at key 
+  · simp_rw [← Quotient.eq''] at key
     refine' Quotient.ind' fun x => _
     refine' Quotient.ind' fun y => _
     exact (key x y).mpr

mathlib commit https://github.com/leanprover-community/mathlib/commit/65a1391a0106c9204fe45bc73a039f056558cb83

@@ -459,7 +459,8 @@ theorem index_mul_card [Fintype G] [hH : Fintype H] : H.index * Fintype.card H =
 
 #print Subgroup.index_dvd_card /-
 @[to_additive]
-theorem index_dvd_card [Fintype G] : H.index ∣ Fintype.card G := by classical
+theorem index_dvd_card [Fintype G] : H.index ∣ Fintype.card G := by
+  classical exact ⟨Fintype.card H, H.index_mul_card.symm⟩
 #align subgroup.index_dvd_card Subgroup.index_dvd_card
 #align add_subgroup.index_dvd_card AddSubgroup.index_dvd_card
 -/

mathlib commit https://github.com/leanprover-community/mathlib/commit/65a1391a0106c9204fe45bc73a039f056558cb83

@@ -459,8 +459,7 @@ theorem index_mul_card [Fintype G] [hH : Fintype H] : H.index * Fintype.card H =
 
 #print Subgroup.index_dvd_card /-
 @[to_additive]
-theorem index_dvd_card [Fintype G] : H.index ∣ Fintype.card G := by
-  classical exact ⟨Fintype.card H, H.index_mul_card.symm⟩
+theorem index_dvd_card [Fintype G] : H.index ∣ Fintype.card G := by classical
 #align subgroup.index_dvd_card Subgroup.index_dvd_card
 #align add_subgroup.index_dvd_card AddSubgroup.index_dvd_card
 -/

mathlib commit https://github.com/leanprover-community/mathlib/commit/ce64cd319bb6b3e82f31c2d38e79080d377be451

@@ -3,9 +3,9 @@ Copyright (c) 2021 Thomas Browning. All rights reserved.
 Released under Apache 2.0 license as described in the file LICENSE.
 Authors: Thomas Browning
 -/
-import Mathbin.Data.Finite.Card
-import Mathbin.GroupTheory.Finiteness
-import Mathbin.GroupTheory.GroupAction.Quotient
+import Data.Finite.Card
+import GroupTheory.Finiteness
+import GroupTheory.GroupAction.Quotient
 
 #align_import group_theory.index from "leanprover-community/mathlib"@"1ead22342e1a078bd44744ace999f85756555d35"
 

mathlib commit https://github.com/leanprover-community/mathlib/commit/63721b2c3eba6c325ecf8ae8cca27155a4f6306f

@@ -112,7 +112,7 @@ variable {H K L}
 @[to_additive relindex_mul_index]
 theorem relindex_mul_index (h : H ≤ K) : H.relindex K * K.index = H.index :=
   ((mul_comm _ _).trans (Cardinal.toNat_mul _ _).symm).trans
-    (congr_arg Cardinal.toNat (Equiv.cardinal_eq (quotientEquivProdOfLe h))).symm
+    (congr_arg Cardinal.toNat (Equiv.cardinal_eq (quotientEquivProdOfLE h))).symm
 #align subgroup.relindex_mul_index Subgroup.relindex_mul_index
 #align add_subgroup.relindex_mul_index AddSubgroup.relindex_mul_index
 -/
@@ -478,7 +478,7 @@ theorem relindex_eq_zero_of_le_left (hHK : H ≤ K) (hKL : K.relindex L = 0) : H
 #print Subgroup.relindex_eq_zero_of_le_right /-
 @[to_additive]
 theorem relindex_eq_zero_of_le_right (hKL : K ≤ L) (hHK : H.relindex K = 0) : H.relindex L = 0 :=
-  Finite.card_eq_zero_of_embedding (quotientSubgroupOfEmbeddingOfLe H hKL) hHK
+  Finite.card_eq_zero_of_embedding (quotientSubgroupOfEmbeddingOfLE H hKL) hHK
 #align subgroup.relindex_eq_zero_of_le_right Subgroup.relindex_eq_zero_of_le_right
 #align add_subgroup.relindex_eq_zero_of_le_right AddSubgroup.relindex_eq_zero_of_le_right
 -/
@@ -504,7 +504,7 @@ theorem relindex_le_of_le_left (hHK : H ≤ K) (hHL : H.relindex L ≠ 0) :
 @[to_additive]
 theorem relindex_le_of_le_right (hKL : K ≤ L) (hHL : H.relindex L ≠ 0) :
     H.relindex K ≤ H.relindex L :=
-  Finite.card_le_of_embedding' (quotientSubgroupOfEmbeddingOfLe H hKL) fun h => (hHL h).elim
+  Finite.card_le_of_embedding' (quotientSubgroupOfEmbeddingOfLE H hKL) fun h => (hHL h).elim
 #align subgroup.relindex_le_of_le_right Subgroup.relindex_le_of_le_right
 #align add_subgroup.relindex_le_of_le_right AddSubgroup.relindex_le_of_le_right
 -/

mathlib commit https://github.com/leanprover-community/mathlib/commit/8ea5598db6caeddde6cb734aa179cc2408dbd345

@@ -2,16 +2,13 @@
 Copyright (c) 2021 Thomas Browning. All rights reserved.
 Released under Apache 2.0 license as described in the file LICENSE.
 Authors: Thomas Browning
-
-! This file was ported from Lean 3 source module group_theory.index
-! leanprover-community/mathlib commit 1ead22342e1a078bd44744ace999f85756555d35
-! Please do not edit these lines, except to modify the commit id
-! if you have ported upstream changes.
 -/
 import Mathbin.Data.Finite.Card
 import Mathbin.GroupTheory.Finiteness
 import Mathbin.GroupTheory.GroupAction.Quotient
 
+#align_import group_theory.index from "leanprover-community/mathlib"@"1ead22342e1a078bd44744ace999f85756555d35"
+
 /-!
 # Index of a Subgroup
 

mathlib commit https://github.com/leanprover-community/mathlib/commit/9fb8964792b4237dac6200193a0d533f1b3f7423

@@ -67,6 +67,7 @@ noncomputable def relindex : ℕ :=
 #align add_subgroup.relindex AddSubgroup.relindex
 -/
 
+#print Subgroup.index_comap_of_surjective /-
 @[to_additive]
 theorem index_comap_of_surjective {G' : Type _} [Group G'] {f : G' →* G}
     (hf : Function.Surjective f) : (H.comap f).index = H.index :=
@@ -87,6 +88,7 @@ theorem index_comap_of_surjective {G' : Type _} [Group G'] {f : G' →* G}
     exact ⟨y, (Quotient.map'_mk'' f _ y).trans (congr_arg Quotient.mk'' hy)⟩
 #align subgroup.index_comap_of_surjective Subgroup.index_comap_of_surjective
 #align add_subgroup.index_comap_of_surjective AddSubgroup.index_comap_of_surjective
+-/
 
 #print Subgroup.index_comap /-
 @[to_additive]
@@ -109,34 +111,43 @@ theorem relindex_comap {G' : Type _} [Group G'] (f : G' →* G) (K : Subgroup G'
 
 variable {H K L}
 
+#print Subgroup.relindex_mul_index /-
 @[to_additive relindex_mul_index]
 theorem relindex_mul_index (h : H ≤ K) : H.relindex K * K.index = H.index :=
   ((mul_comm _ _).trans (Cardinal.toNat_mul _ _).symm).trans
     (congr_arg Cardinal.toNat (Equiv.cardinal_eq (quotientEquivProdOfLe h))).symm
 #align subgroup.relindex_mul_index Subgroup.relindex_mul_index
 #align add_subgroup.relindex_mul_index AddSubgroup.relindex_mul_index
+-/
 
+#print Subgroup.index_dvd_of_le /-
 @[to_additive]
 theorem index_dvd_of_le (h : H ≤ K) : K.index ∣ H.index :=
   dvd_of_mul_left_eq (H.relindex K) (relindex_mul_index h)
 #align subgroup.index_dvd_of_le Subgroup.index_dvd_of_le
 #align add_subgroup.index_dvd_of_le AddSubgroup.index_dvd_of_le
+-/
 
+#print Subgroup.relindex_dvd_index_of_le /-
 @[to_additive]
 theorem relindex_dvd_index_of_le (h : H ≤ K) : H.relindex K ∣ H.index :=
   dvd_of_mul_right_eq K.index (relindex_mul_index h)
 #align subgroup.relindex_dvd_index_of_le Subgroup.relindex_dvd_index_of_le
 #align add_subgroup.relindex_dvd_index_of_le AddSubgroup.relindex_dvd_index_of_le
+-/
 
+#print Subgroup.relindex_subgroupOf /-
 @[to_additive]
 theorem relindex_subgroupOf (hKL : K ≤ L) :
     (H.subgroupOf L).relindex (K.subgroupOf L) = H.relindex K :=
   ((index_comap (H.subgroupOf L) (inclusion hKL)).trans (congr_arg _ (inclusion_range hKL))).symm
 #align subgroup.relindex_subgroup_of Subgroup.relindex_subgroupOf
 #align add_subgroup.relindex_add_subgroup_of AddSubgroup.relindex_addSubgroupOf
+-/
 
 variable (H K L)
 
+#print Subgroup.relindex_mul_relindex /-
 @[to_additive relindex_mul_relindex]
 theorem relindex_mul_relindex (hHK : H ≤ K) (hKL : K ≤ L) :
     H.relindex K * K.relindex L = H.relindex L :=
@@ -145,37 +156,48 @@ theorem relindex_mul_relindex (hHK : H ≤ K) (hKL : K ≤ L) :
   exact relindex_mul_index fun x hx => hHK hx
 #align subgroup.relindex_mul_relindex Subgroup.relindex_mul_relindex
 #align add_subgroup.relindex_mul_relindex AddSubgroup.relindex_mul_relindex
+-/
 
+#print Subgroup.inf_relindex_right /-
 @[to_additive]
 theorem inf_relindex_right : (H ⊓ K).relindex K = H.relindex K := by
   rw [relindex, relindex, inf_subgroup_of_right]
 #align subgroup.inf_relindex_right Subgroup.inf_relindex_right
 #align add_subgroup.inf_relindex_right AddSubgroup.inf_relindex_right
+-/
 
+#print Subgroup.inf_relindex_left /-
 @[to_additive]
 theorem inf_relindex_left : (H ⊓ K).relindex H = K.relindex H := by
   rw [inf_comm, inf_relindex_right]
 #align subgroup.inf_relindex_left Subgroup.inf_relindex_left
 #align add_subgroup.inf_relindex_left AddSubgroup.inf_relindex_left
+-/
 
+#print Subgroup.relindex_inf_mul_relindex /-
 @[to_additive relindex_inf_mul_relindex]
 theorem relindex_inf_mul_relindex : H.relindex (K ⊓ L) * K.relindex L = (H ⊓ K).relindex L := by
   rw [← inf_relindex_right H (K ⊓ L), ← inf_relindex_right K L, ← inf_relindex_right (H ⊓ K) L,
     inf_assoc, relindex_mul_relindex (H ⊓ (K ⊓ L)) (K ⊓ L) L inf_le_right inf_le_right]
 #align subgroup.relindex_inf_mul_relindex Subgroup.relindex_inf_mul_relindex
 #align add_subgroup.relindex_inf_mul_relindex AddSubgroup.relindex_inf_mul_relindex
+-/
 
+#print Subgroup.relindex_sup_right /-
 @[simp, to_additive]
 theorem relindex_sup_right [K.Normal] : K.relindex (H ⊔ K) = K.relindex H :=
   Nat.card_congr (QuotientGroup.quotientInfEquivProdNormalQuotient H K).toEquiv.symm
 #align subgroup.relindex_sup_right Subgroup.relindex_sup_right
 #align add_subgroup.relindex_sup_right AddSubgroup.relindex_sup_right
+-/
 
+#print Subgroup.relindex_sup_left /-
 @[simp, to_additive]
 theorem relindex_sup_left [K.Normal] : K.relindex (K ⊔ H) = K.relindex H := by
   rw [sup_comm, relindex_sup_right]
 #align subgroup.relindex_sup_left Subgroup.relindex_sup_left
 #align add_subgroup.relindex_sup_left AddSubgroup.relindex_sup_left
+-/
 
 #print Subgroup.relindex_dvd_index_of_normal /-
 @[to_additive]
@@ -187,12 +209,15 @@ theorem relindex_dvd_index_of_normal [H.Normal] : H.relindex K ∣ H.index :=
 
 variable {H K}
 
+#print Subgroup.relindex_dvd_of_le_left /-
 @[to_additive]
 theorem relindex_dvd_of_le_left (hHK : H ≤ K) : K.relindex L ∣ H.relindex L :=
   inf_of_le_left hHK ▸ dvd_of_mul_left_eq _ (relindex_inf_mul_relindex _ _ _)
 #align subgroup.relindex_dvd_of_le_left Subgroup.relindex_dvd_of_le_left
 #align add_subgroup.relindex_dvd_of_le_left AddSubgroup.relindex_dvd_of_le_left
+-/
 
+#print Subgroup.index_eq_two_iff /-
 /-- A subgroup has index two if and only if there exists `a` such that for all `b`, exactly one
 of `b * a` and `b` belong to `H`. -/
 @[to_additive
@@ -210,7 +235,9 @@ theorem index_eq_two_iff : H.index = 2 ↔ ∃ a, ∀ b, Xor' (b * a ∈ H) (b 
   · rwa [ha, inv_mem_iff]
 #align subgroup.index_eq_two_iff Subgroup.index_eq_two_iff
 #align add_subgroup.index_eq_two_iff AddSubgroup.index_eq_two_iff
+-/
 
+#print Subgroup.mul_mem_iff_of_index_two /-
 @[to_additive]
 theorem mul_mem_iff_of_index_two (h : H.index = 2) {a b : G} : a * b ∈ H ↔ (a ∈ H ↔ b ∈ H) :=
   by
@@ -222,67 +249,88 @@ theorem mul_mem_iff_of_index_two (h : H.index = 2) {a b : G} : a * b ∈ H ↔ (
   rwa [mul_assoc, mul_mem_cancel_right ((hc _).Or.resolve_right hb)]
 #align subgroup.mul_mem_iff_of_index_two Subgroup.mul_mem_iff_of_index_two
 #align add_subgroup.add_mem_iff_of_index_two AddSubgroup.add_mem_iff_of_index_two
+-/
 
+#print Subgroup.mul_self_mem_of_index_two /-
 @[to_additive]
 theorem mul_self_mem_of_index_two (h : H.index = 2) (a : G) : a * a ∈ H := by
   rw [mul_mem_iff_of_index_two h]
 #align subgroup.mul_self_mem_of_index_two Subgroup.mul_self_mem_of_index_two
 #align add_subgroup.add_self_mem_of_index_two AddSubgroup.add_self_mem_of_index_two
+-/
 
+#print Subgroup.sq_mem_of_index_two /-
 @[to_additive two_smul_mem_of_index_two]
 theorem sq_mem_of_index_two (h : H.index = 2) (a : G) : a ^ 2 ∈ H :=
   (pow_two a).symm ▸ mul_self_mem_of_index_two h a
 #align subgroup.sq_mem_of_index_two Subgroup.sq_mem_of_index_two
 #align add_subgroup.two_smul_mem_of_index_two AddSubgroup.two_smul_mem_of_index_two
+-/
 
 variable (H K)
 
+#print Subgroup.index_top /-
 @[simp, to_additive]
 theorem index_top : (⊤ : Subgroup G).index = 1 :=
   Cardinal.toNat_eq_one_iff_unique.mpr ⟨QuotientGroup.subsingleton_quotient_top, ⟨1⟩⟩
 #align subgroup.index_top Subgroup.index_top
 #align add_subgroup.index_top AddSubgroup.index_top
+-/
 
+#print Subgroup.index_bot /-
 @[simp, to_additive]
 theorem index_bot : (⊥ : Subgroup G).index = Nat.card G :=
   Cardinal.toNat_congr QuotientGroup.quotientBot.toEquiv
 #align subgroup.index_bot Subgroup.index_bot
 #align add_subgroup.index_bot AddSubgroup.index_bot
+-/
 
+#print Subgroup.index_bot_eq_card /-
 @[to_additive]
 theorem index_bot_eq_card [Fintype G] : (⊥ : Subgroup G).index = Fintype.card G :=
   index_bot.trans Nat.card_eq_fintype_card
 #align subgroup.index_bot_eq_card Subgroup.index_bot_eq_card
 #align add_subgroup.index_bot_eq_card AddSubgroup.index_bot_eq_card
+-/
 
+#print Subgroup.relindex_top_left /-
 @[simp, to_additive]
 theorem relindex_top_left : (⊤ : Subgroup G).relindex H = 1 :=
   index_top
 #align subgroup.relindex_top_left Subgroup.relindex_top_left
 #align add_subgroup.relindex_top_left AddSubgroup.relindex_top_left
+-/
 
+#print Subgroup.relindex_top_right /-
 @[simp, to_additive]
 theorem relindex_top_right : H.relindex ⊤ = H.index := by
   rw [← relindex_mul_index (show H ≤ ⊤ from le_top), index_top, mul_one]
 #align subgroup.relindex_top_right Subgroup.relindex_top_right
 #align add_subgroup.relindex_top_right AddSubgroup.relindex_top_right
+-/
 
+#print Subgroup.relindex_bot_left /-
 @[simp, to_additive]
 theorem relindex_bot_left : (⊥ : Subgroup G).relindex H = Nat.card H := by
   rw [relindex, bot_subgroup_of, index_bot]
 #align subgroup.relindex_bot_left Subgroup.relindex_bot_left
 #align add_subgroup.relindex_bot_left AddSubgroup.relindex_bot_left
+-/
 
+#print Subgroup.relindex_bot_left_eq_card /-
 @[to_additive]
 theorem relindex_bot_left_eq_card [Fintype H] : (⊥ : Subgroup G).relindex H = Fintype.card H :=
   H.relindex_bot_left.trans Nat.card_eq_fintype_card
 #align subgroup.relindex_bot_left_eq_card Subgroup.relindex_bot_left_eq_card
 #align add_subgroup.relindex_bot_left_eq_card AddSubgroup.relindex_bot_left_eq_card
+-/
 
+#print Subgroup.relindex_bot_right /-
 @[simp, to_additive]
 theorem relindex_bot_right : H.relindex ⊥ = 1 := by rw [relindex, subgroup_of_bot_eq_top, index_top]
 #align subgroup.relindex_bot_right Subgroup.relindex_bot_right
 #align add_subgroup.relindex_bot_right AddSubgroup.relindex_bot_right
+-/
 
 #print Subgroup.relindex_self /-
 @[simp, to_additive]
@@ -291,25 +339,32 @@ theorem relindex_self : H.relindex H = 1 := by rw [relindex, subgroup_of_self, i
 #align add_subgroup.relindex_self AddSubgroup.relindex_self
 -/
 
+#print Subgroup.index_ker /-
 @[to_additive]
 theorem index_ker {H} [Group H] (f : G →* H) : f.ker.index = Nat.card (Set.range f) := by
   rw [← MonoidHom.comap_bot, index_comap, relindex_bot_left]; rfl
 #align subgroup.index_ker Subgroup.index_ker
 #align add_subgroup.index_ker AddSubgroup.index_ker
+-/
 
+#print Subgroup.relindex_ker /-
 @[to_additive]
 theorem relindex_ker {H} [Group H] (f : G →* H) (K : Subgroup G) :
     f.ker.relindex K = Nat.card (f '' K) := by
   rw [← MonoidHom.comap_bot, relindex_comap, relindex_bot_left]; rfl
 #align subgroup.relindex_ker Subgroup.relindex_ker
 #align add_subgroup.relindex_ker AddSubgroup.relindex_ker
+-/
 
+#print Subgroup.card_mul_index /-
 @[simp, to_additive card_mul_index]
 theorem card_mul_index : Nat.card H * H.index = Nat.card G := by
   rw [← relindex_bot_left, ← index_bot]; exact relindex_mul_index bot_le
 #align subgroup.card_mul_index Subgroup.card_mul_index
 #align add_subgroup.card_mul_index AddSubgroup.card_mul_index
+-/
 
+#print Subgroup.nat_card_dvd_of_injective /-
 @[to_additive]
 theorem nat_card_dvd_of_injective {G H : Type _} [Group G] [Group H] (f : G →* H)
     (hf : Function.Injective f) : Nat.card G ∣ Nat.card H :=
@@ -318,13 +373,17 @@ theorem nat_card_dvd_of_injective {G H : Type _} [Group G] [Group H] (f : G →*
   exact Dvd.intro f.range.index f.range.card_mul_index
 #align subgroup.nat_card_dvd_of_injective Subgroup.nat_card_dvd_of_injective
 #align add_subgroup.nat_card_dvd_of_injective AddSubgroup.nat_card_dvd_of_injective
+-/
 
+#print Subgroup.nat_card_dvd_of_le /-
 @[to_additive]
 theorem nat_card_dvd_of_le (hHK : H ≤ K) : Nat.card H ∣ Nat.card K :=
   nat_card_dvd_of_injective (inclusion hHK) (inclusion_injective hHK)
 #align subgroup.nat_card_dvd_of_le Subgroup.nat_card_dvd_of_le
 #align add_subgroup.nat_card_dvd_of_le AddSubgroup.nat_card_dvd_of_le
+-/
 
+#print Subgroup.nat_card_dvd_of_surjective /-
 @[to_additive]
 theorem nat_card_dvd_of_surjective {G H : Type _} [Group G] [Group H] (f : G →* H)
     (hf : Function.Surjective f) : Nat.card H ∣ Nat.card G :=
@@ -333,21 +392,27 @@ theorem nat_card_dvd_of_surjective {G H : Type _} [Group G] [Group H] (f : G →
   exact Dvd.intro_left (Nat.card f.ker) f.ker.card_mul_index
 #align subgroup.nat_card_dvd_of_surjective Subgroup.nat_card_dvd_of_surjective
 #align add_subgroup.nat_card_dvd_of_surjective AddSubgroup.nat_card_dvd_of_surjective
+-/
 
+#print Subgroup.card_dvd_of_surjective /-
 @[to_additive]
 theorem card_dvd_of_surjective {G H : Type _} [Group G] [Group H] [Fintype G] [Fintype H]
     (f : G →* H) (hf : Function.Surjective f) : Fintype.card H ∣ Fintype.card G := by
   simp only [← Nat.card_eq_fintype_card, nat_card_dvd_of_surjective f hf]
 #align subgroup.card_dvd_of_surjective Subgroup.card_dvd_of_surjective
 #align add_subgroup.card_dvd_of_surjective AddSubgroup.card_dvd_of_surjective
+-/
 
+#print Subgroup.index_map /-
 @[to_additive]
 theorem index_map {G' : Type _} [Group G'] (f : G →* G') :
     (H.map f).index = (H ⊔ f.ker).index * f.range.index := by
   rw [← comap_map_eq, index_comap, relindex_mul_index (H.map_le_range f)]
 #align subgroup.index_map Subgroup.index_map
 #align add_subgroup.index_map AddSubgroup.index_map
+-/
 
+#print Subgroup.index_map_dvd /-
 @[to_additive]
 theorem index_map_dvd {G' : Type _} [Group G'] {f : G →* G'} (hf : Function.Surjective f) :
     (H.map f).index ∣ H.index :=
@@ -356,7 +421,9 @@ theorem index_map_dvd {G' : Type _} [Group G'] {f : G →* G'} (hf : Function.Su
   exact index_dvd_of_le le_sup_left
 #align subgroup.index_map_dvd Subgroup.index_map_dvd
 #align add_subgroup.index_map_dvd AddSubgroup.index_map_dvd
+-/
 
+#print Subgroup.dvd_index_map /-
 @[to_additive]
 theorem dvd_index_map {G' : Type _} [Group G'] {f : G →* G'} (hf : f.ker ≤ H) :
     H.index ∣ (H.map f).index := by
@@ -364,13 +431,16 @@ theorem dvd_index_map {G' : Type _} [Group G'] {f : G →* G'} (hf : f.ker ≤ H
   apply dvd_mul_right
 #align subgroup.dvd_index_map Subgroup.dvd_index_map
 #align add_subgroup.dvd_index_map AddSubgroup.dvd_index_map
+-/
 
+#print Subgroup.index_map_eq /-
 @[to_additive]
 theorem index_map_eq {G' : Type _} [Group G'] {f : G →* G'} (hf1 : Function.Surjective f)
     (hf2 : f.ker ≤ H) : (H.map f).index = H.index :=
   Nat.dvd_antisymm (H.index_map_dvd hf1) (H.dvd_index_map hf2)
 #align subgroup.index_map_eq Subgroup.index_map_eq
 #align add_subgroup.index_map_eq AddSubgroup.index_map_eq
+-/
 
 #print Subgroup.index_eq_card /-
 @[to_additive]
@@ -380,6 +450,7 @@ theorem index_eq_card [Fintype (G ⧸ H)] : H.index = Fintype.card (G ⧸ H) :=
 #align add_subgroup.index_eq_card AddSubgroup.index_eq_card
 -/
 
+#print Subgroup.index_mul_card /-
 @[to_additive index_mul_card]
 theorem index_mul_card [Fintype G] [hH : Fintype H] : H.index * Fintype.card H = Fintype.card G :=
   by
@@ -387,6 +458,7 @@ theorem index_mul_card [Fintype G] [hH : Fintype H] : H.index * Fintype.card H =
     exact relindex_mul_index bot_le
 #align subgroup.index_mul_card Subgroup.index_mul_card
 #align add_subgroup.index_mul_card AddSubgroup.index_mul_card
+-/
 
 #print Subgroup.index_dvd_card /-
 @[to_additive]
@@ -398,17 +470,21 @@ theorem index_dvd_card [Fintype G] : H.index ∣ Fintype.card G := by
 
 variable {H K L}
 
+#print Subgroup.relindex_eq_zero_of_le_left /-
 @[to_additive]
 theorem relindex_eq_zero_of_le_left (hHK : H ≤ K) (hKL : K.relindex L = 0) : H.relindex L = 0 :=
   eq_zero_of_zero_dvd (hKL ▸ relindex_dvd_of_le_left L hHK)
 #align subgroup.relindex_eq_zero_of_le_left Subgroup.relindex_eq_zero_of_le_left
 #align add_subgroup.relindex_eq_zero_of_le_left AddSubgroup.relindex_eq_zero_of_le_left
+-/
 
+#print Subgroup.relindex_eq_zero_of_le_right /-
 @[to_additive]
 theorem relindex_eq_zero_of_le_right (hKL : K ≤ L) (hHK : H.relindex K = 0) : H.relindex L = 0 :=
   Finite.card_eq_zero_of_embedding (quotientSubgroupOfEmbeddingOfLe H hKL) hHK
 #align subgroup.relindex_eq_zero_of_le_right Subgroup.relindex_eq_zero_of_le_right
 #align add_subgroup.relindex_eq_zero_of_le_right AddSubgroup.relindex_eq_zero_of_le_right
+-/
 
 #print Subgroup.index_eq_zero_of_relindex_eq_zero /-
 @[to_additive]
@@ -418,19 +494,23 @@ theorem index_eq_zero_of_relindex_eq_zero (h : H.relindex K = 0) : H.index = 0 :
 #align add_subgroup.index_eq_zero_of_relindex_eq_zero AddSubgroup.index_eq_zero_of_relindex_eq_zero
 -/
 
+#print Subgroup.relindex_le_of_le_left /-
 @[to_additive]
 theorem relindex_le_of_le_left (hHK : H ≤ K) (hHL : H.relindex L ≠ 0) :
     K.relindex L ≤ H.relindex L :=
   Nat.le_of_dvd (Nat.pos_of_ne_zero hHL) (relindex_dvd_of_le_left L hHK)
 #align subgroup.relindex_le_of_le_left Subgroup.relindex_le_of_le_left
 #align add_subgroup.relindex_le_of_le_left AddSubgroup.relindex_le_of_le_left
+-/
 
+#print Subgroup.relindex_le_of_le_right /-
 @[to_additive]
 theorem relindex_le_of_le_right (hKL : K ≤ L) (hHL : H.relindex L ≠ 0) :
     H.relindex K ≤ H.relindex L :=
   Finite.card_le_of_embedding' (quotientSubgroupOfEmbeddingOfLe H hKL) fun h => (hHL h).elim
 #align subgroup.relindex_le_of_le_right Subgroup.relindex_le_of_le_right
 #align add_subgroup.relindex_le_of_le_right AddSubgroup.relindex_le_of_le_right
+-/
 
 #print Subgroup.relindex_ne_zero_trans /-
 @[to_additive]
@@ -442,6 +522,7 @@ theorem relindex_ne_zero_trans (hHK : H.relindex K ≠ 0) (hKL : K.relindex L 
 #align add_subgroup.relindex_ne_zero_trans AddSubgroup.relindex_ne_zero_trans
 -/
 
+#print Subgroup.relindex_inf_ne_zero /-
 @[to_additive]
 theorem relindex_inf_ne_zero (hH : H.relindex L ≠ 0) (hK : K.relindex L ≠ 0) :
     (H ⊓ K).relindex L ≠ 0 :=
@@ -452,7 +533,9 @@ theorem relindex_inf_ne_zero (hH : H.relindex L ≠ 0) (hK : K.relindex L ≠ 0)
   exact relindex_ne_zero_trans hH hK
 #align subgroup.relindex_inf_ne_zero Subgroup.relindex_inf_ne_zero
 #align add_subgroup.relindex_inf_ne_zero AddSubgroup.relindex_inf_ne_zero
+-/
 
+#print Subgroup.index_inf_ne_zero /-
 @[to_additive]
 theorem index_inf_ne_zero (hH : H.index ≠ 0) (hK : K.index ≠ 0) : (H ⊓ K).index ≠ 0 :=
   by
@@ -460,7 +543,9 @@ theorem index_inf_ne_zero (hH : H.index ≠ 0) (hK : K.index ≠ 0) : (H ⊓ K).
   exact relindex_inf_ne_zero hH hK
 #align subgroup.index_inf_ne_zero Subgroup.index_inf_ne_zero
 #align add_subgroup.index_inf_ne_zero AddSubgroup.index_inf_ne_zero
+-/
 
+#print Subgroup.relindex_inf_le /-
 @[to_additive]
 theorem relindex_inf_le : (H ⊓ K).relindex L ≤ H.relindex L * K.relindex L :=
   by
@@ -471,12 +556,15 @@ theorem relindex_inf_le : (H ⊓ K).relindex L ≤ H.relindex L * K.relindex L :
   exact mul_le_mul_right' (relindex_le_of_le_right inf_le_right h) (K.relindex L)
 #align subgroup.relindex_inf_le Subgroup.relindex_inf_le
 #align add_subgroup.relindex_inf_le AddSubgroup.relindex_inf_le
+-/
 
+#print Subgroup.index_inf_le /-
 @[to_additive]
 theorem index_inf_le : (H ⊓ K).index ≤ H.index * K.index := by
   simp_rw [← relindex_top_right, relindex_inf_le]
 #align subgroup.index_inf_le Subgroup.index_inf_le
 #align add_subgroup.index_inf_le AddSubgroup.index_inf_le
+-/
 
 #print Subgroup.relindex_iInf_ne_zero /-
 @[to_additive]
@@ -522,6 +610,7 @@ theorem index_iInf_le {ι : Type _} [Fintype ι] (f : ι → Subgroup G) :
 #align add_subgroup.index_infi_le AddSubgroup.index_iInf_le
 -/
 
+#print Subgroup.index_eq_one /-
 @[simp, to_additive index_eq_one]
 theorem index_eq_one : H.index = 1 ↔ H = ⊤ :=
   ⟨fun h =>
@@ -529,18 +618,23 @@ theorem index_eq_one : H.index = 1 ↔ H = ⊤ :=
     fun h => (congr_arg index h).trans index_top⟩
 #align subgroup.index_eq_one Subgroup.index_eq_one
 #align add_subgroup.index_eq_one AddSubgroup.index_eq_one
+-/
 
+#print Subgroup.relindex_eq_one /-
 @[simp, to_additive relindex_eq_one]
 theorem relindex_eq_one : H.relindex K = 1 ↔ K ≤ H :=
   index_eq_one.trans subgroupOf_eq_top
 #align subgroup.relindex_eq_one Subgroup.relindex_eq_one
 #align add_subgroup.relindex_eq_one AddSubgroup.relindex_eq_one
+-/
 
+#print Subgroup.card_eq_one /-
 @[simp, to_additive card_eq_one]
 theorem card_eq_one : Nat.card H = 1 ↔ H = ⊥ :=
   H.relindex_bot_left ▸ relindex_eq_one.trans le_bot_iff
 #align subgroup.card_eq_one Subgroup.card_eq_one
 #align add_subgroup.card_eq_one AddSubgroup.card_eq_one
+-/
 
 #print Subgroup.index_ne_zero_of_finite /-
 @[to_additive]
@@ -559,11 +653,13 @@ noncomputable def fintypeOfIndexNeZero (hH : H.index ≠ 0) : Fintype (G ⧸ H)
 #align add_subgroup.fintype_of_index_ne_zero AddSubgroup.fintypeOfIndexNeZero
 -/
 
+#print Subgroup.one_lt_index_of_ne_top /-
 @[to_additive one_lt_index_of_ne_top]
 theorem one_lt_index_of_ne_top [Finite (G ⧸ H)] (hH : H ≠ ⊤) : 1 < H.index :=
   Nat.one_lt_iff_ne_zero_and_ne_one.mpr ⟨index_ne_zero_of_finite, mt index_eq_one.mp hH⟩
 #align subgroup.one_lt_index_of_ne_top Subgroup.one_lt_index_of_ne_top
 #align add_subgroup.one_lt_index_of_ne_top AddSubgroup.one_lt_index_of_ne_top
+-/
 
 section FiniteIndex
 
@@ -626,14 +722,17 @@ instance [FiniteIndex H] [FiniteIndex K] : FiniteIndex (H ⊓ K) :=
 
 variable {H K}
 
+#print Subgroup.finiteIndex_of_le /-
 @[to_additive]
 theorem finiteIndex_of_le [FiniteIndex H] (h : H ≤ K) : FiniteIndex K :=
   ⟨ne_zero_of_dvd_ne_zero FiniteIndex.finiteIndex (index_dvd_of_le h)⟩
 #align subgroup.finite_index_of_le Subgroup.finiteIndex_of_le
 #align add_subgroup.finite_index_of_le AddSubgroup.finiteIndex_of_le
+-/
 
 variable (H K)
 
+#print Subgroup.finiteIndex_ker /-
 @[to_additive]
 instance finiteIndex_ker {G' : Type _} [Group G'] (f : G →* G') [Finite f.range] :
     f.ker.FiniteIndex :=
@@ -641,6 +740,7 @@ instance finiteIndex_ker {G' : Type _} [Group G'] (f : G →* G') [Finite f.rang
     (Finite.of_equiv f.range (QuotientGroup.quotientKerEquivRange f).symm)
 #align subgroup.finite_index_ker Subgroup.finiteIndex_ker
 #align add_subgroup.finite_index_ker AddSubgroup.finiteIndex_ker
+-/
 
 #print Subgroup.finiteIndex_normalCore /-
 instance finiteIndex_normalCore [H.FiniteIndex] : H.normalCore.FiniteIndex :=

mathlib commit https://github.com/leanprover-community/mathlib/commit/cca40788df1b8755d5baf17ab2f27dacc2e17acb

@@ -78,7 +78,7 @@ theorem index_comap_of_surjective {G' : Type _} [Group G'] {f : G' →* G}
     simp only [QuotientGroup.leftRel_apply]
     exact fun x y => iff_of_eq (congr_arg (· ∈ H) (by rw [f.map_mul, f.map_inv]))
   refine' Cardinal.toNat_congr (Equiv.ofBijective (Quotient.map' f fun x y => (key x y).mp) ⟨_, _⟩)
-  · simp_rw [← Quotient.eq''] at key
+  · simp_rw [← Quotient.eq''] at key 
     refine' Quotient.ind' fun x => _
     refine' Quotient.ind' fun y => _
     exact (key x y).mpr
@@ -447,7 +447,7 @@ theorem relindex_inf_ne_zero (hH : H.relindex L ≠ 0) (hK : K.relindex L ≠ 0)
     (H ⊓ K).relindex L ≠ 0 :=
   by
   replace hH : H.relindex (K ⊓ L) ≠ 0 := mt (relindex_eq_zero_of_le_right inf_le_right) hH
-  rw [← inf_relindex_right] at hH hK⊢
+  rw [← inf_relindex_right] at hH hK ⊢
   rw [inf_assoc]
   exact relindex_ne_zero_trans hH hK
 #align subgroup.relindex_inf_ne_zero Subgroup.relindex_inf_ne_zero
@@ -456,7 +456,7 @@ theorem relindex_inf_ne_zero (hH : H.relindex L ≠ 0) (hK : K.relindex L ≠ 0)
 @[to_additive]
 theorem index_inf_ne_zero (hH : H.index ≠ 0) (hK : K.index ≠ 0) : (H ⊓ K).index ≠ 0 :=
   by
-  rw [← relindex_top_right] at hH hK⊢
+  rw [← relindex_top_right] at hH hK ⊢
   exact relindex_inf_ne_zero hH hK
 #align subgroup.index_inf_ne_zero Subgroup.index_inf_ne_zero
 #align add_subgroup.index_inf_ne_zero AddSubgroup.index_inf_ne_zero
@@ -508,7 +508,7 @@ theorem relindex_iInf_le {ι : Type _} [Fintype ι] (f : ι → Subgroup G) :
 theorem index_iInf_ne_zero {ι : Type _} [Finite ι] {f : ι → Subgroup G}
     (hf : ∀ i, (f i).index ≠ 0) : (⨅ i, f i).index ≠ 0 :=
   by
-  simp_rw [← relindex_top_right] at hf⊢
+  simp_rw [← relindex_top_right] at hf ⊢
   exact relindex_infi_ne_zero hf
 #align subgroup.index_infi_ne_zero Subgroup.index_iInf_ne_zero
 #align add_subgroup.index_infi_ne_zero AddSubgroup.index_iInf_ne_zero

mathlib commit https://github.com/leanprover-community/mathlib/commit/917c3c072e487b3cccdbfeff17e75b40e45f66cb

@@ -42,7 +42,7 @@ Several theorems proved in this file are known as Lagrange's theorem.
 
 namespace Subgroup
 
-open BigOperators Cardinal
+open scoped BigOperators Cardinal
 
 variable {G : Type _} [Group G] (H K L : Subgroup G)
 

mathlib commit https://github.com/leanprover-community/mathlib/commit/917c3c072e487b3cccdbfeff17e75b40e45f66cb

@@ -67,12 +67,6 @@ noncomputable def relindex : ℕ :=
 #align add_subgroup.relindex AddSubgroup.relindex
 -/
 
-/- warning: subgroup.index_comap_of_surjective -> Subgroup.index_comap_of_surjective is a dubious translation:
-lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) {G' : Type.{u2}} [_inst_2 : Group.{u2} G'] {f : MonoidHom.{u2, u1} G' G (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))}, (Function.Surjective.{succ u2, succ u1} G' G (coeFn.{max (succ u1) (succ u2), max (succ u2) (succ u1)} (MonoidHom.{u2, u1} G' G (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) (fun (_x : MonoidHom.{u2, u1} G' G (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) => G' -> G) (MonoidHom.hasCoeToFun.{u2, u1} G' G (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) f)) -> (Eq.{1} Nat (Subgroup.index.{u2} G' _inst_2 (Subgroup.comap.{u2, u1} G' _inst_2 G _inst_1 f H)) (Subgroup.index.{u1} G _inst_1 H))
-but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) {G' : Type.{u2}} [_inst_2 : Group.{u2} G'] {f : MonoidHom.{u2, u1} G' G (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))}, (Function.Surjective.{succ u2, succ u1} G' G (FunLike.coe.{max (succ u1) (succ u2), succ u2, succ u1} (MonoidHom.{u2, u1} G' G (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) G' (fun (_x : G') => (fun (x._@.Mathlib.Algebra.Hom.Group._hyg.2397 : G') => G) _x) (MulHomClass.toFunLike.{max u1 u2, u2, u1} (MonoidHom.{u2, u1} G' G (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) G' G (MulOneClass.toMul.{u2} G' (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) (MulOneClass.toMul.{u1} G (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) (MonoidHomClass.toMulHomClass.{max u1 u2, u2, u1} (MonoidHom.{u2, u1} G' G (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) G' G (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (MonoidHom.monoidHomClass.{u2, u1} G' G (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))))) f)) -> (Eq.{1} Nat (Subgroup.index.{u2} G' _inst_2 (Subgroup.comap.{u2, u1} G' _inst_2 G _inst_1 f H)) (Subgroup.index.{u1} G _inst_1 H))
-Case conversion may be inaccurate. Consider using '#align subgroup.index_comap_of_surjective Subgroup.index_comap_of_surjectiveₓ'. -/
 @[to_additive]
 theorem index_comap_of_surjective {G' : Type _} [Group G'] {f : G' →* G}
     (hf : Function.Surjective f) : (H.comap f).index = H.index :=
@@ -115,12 +109,6 @@ theorem relindex_comap {G' : Type _} [Group G'] (f : G' →* G) (K : Subgroup G'
 
 variable {H K L}
 
-/- warning: subgroup.relindex_mul_index -> Subgroup.relindex_mul_index is a dubious translation:
-lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1}, (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toHasLe.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (SetLike.partialOrder.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)))) H K) -> (Eq.{1} Nat (HMul.hMul.{0, 0, 0} Nat Nat Nat (instHMul.{0} Nat Nat.hasMul) (Subgroup.relindex.{u1} G _inst_1 H K) (Subgroup.index.{u1} G _inst_1 K)) (Subgroup.index.{u1} G _inst_1 H))
-but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1}, (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toLE.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (CompleteSemilatticeInf.toPartialOrder.{u1} (Subgroup.{u1} G _inst_1) (CompleteLattice.toCompleteSemilatticeInf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instCompleteLatticeSubgroup.{u1} G _inst_1))))) H K) -> (Eq.{1} Nat (HMul.hMul.{0, 0, 0} Nat Nat Nat (instHMul.{0} Nat instMulNat) (Subgroup.relindex.{u1} G _inst_1 H K) (Subgroup.index.{u1} G _inst_1 K)) (Subgroup.index.{u1} G _inst_1 H))
-Case conversion may be inaccurate. Consider using '#align subgroup.relindex_mul_index Subgroup.relindex_mul_indexₓ'. -/
 @[to_additive relindex_mul_index]
 theorem relindex_mul_index (h : H ≤ K) : H.relindex K * K.index = H.index :=
   ((mul_comm _ _).trans (Cardinal.toNat_mul _ _).symm).trans
@@ -128,36 +116,18 @@ theorem relindex_mul_index (h : H ≤ K) : H.relindex K * K.index = H.index :=
 #align subgroup.relindex_mul_index Subgroup.relindex_mul_index
 #align add_subgroup.relindex_mul_index AddSubgroup.relindex_mul_index
 
-/- warning: subgroup.index_dvd_of_le -> Subgroup.index_dvd_of_le is a dubious translation:
-lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1}, (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toHasLe.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (SetLike.partialOrder.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)))) H K) -> (Dvd.Dvd.{0} Nat Nat.hasDvd (Subgroup.index.{u1} G _inst_1 K) (Subgroup.index.{u1} G _inst_1 H))
-but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1}, (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toLE.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (CompleteSemilatticeInf.toPartialOrder.{u1} (Subgroup.{u1} G _inst_1) (CompleteLattice.toCompleteSemilatticeInf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instCompleteLatticeSubgroup.{u1} G _inst_1))))) H K) -> (Dvd.dvd.{0} Nat Nat.instDvdNat (Subgroup.index.{u1} G _inst_1 K) (Subgroup.index.{u1} G _inst_1 H))
-Case conversion may be inaccurate. Consider using '#align subgroup.index_dvd_of_le Subgroup.index_dvd_of_leₓ'. -/
 @[to_additive]
 theorem index_dvd_of_le (h : H ≤ K) : K.index ∣ H.index :=
   dvd_of_mul_left_eq (H.relindex K) (relindex_mul_index h)
 #align subgroup.index_dvd_of_le Subgroup.index_dvd_of_le
 #align add_subgroup.index_dvd_of_le AddSubgroup.index_dvd_of_le
 
-/- warning: subgroup.relindex_dvd_index_of_le -> Subgroup.relindex_dvd_index_of_le is a dubious translation:
-lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1}, (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toHasLe.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (SetLike.partialOrder.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)))) H K) -> (Dvd.Dvd.{0} Nat Nat.hasDvd (Subgroup.relindex.{u1} G _inst_1 H K) (Subgroup.index.{u1} G _inst_1 H))
-but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1}, (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toLE.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (CompleteSemilatticeInf.toPartialOrder.{u1} (Subgroup.{u1} G _inst_1) (CompleteLattice.toCompleteSemilatticeInf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instCompleteLatticeSubgroup.{u1} G _inst_1))))) H K) -> (Dvd.dvd.{0} Nat Nat.instDvdNat (Subgroup.relindex.{u1} G _inst_1 H K) (Subgroup.index.{u1} G _inst_1 H))
-Case conversion may be inaccurate. Consider using '#align subgroup.relindex_dvd_index_of_le Subgroup.relindex_dvd_index_of_leₓ'. -/
 @[to_additive]
 theorem relindex_dvd_index_of_le (h : H ≤ K) : H.relindex K ∣ H.index :=
   dvd_of_mul_right_eq K.index (relindex_mul_index h)
 #align subgroup.relindex_dvd_index_of_le Subgroup.relindex_dvd_index_of_le
 #align add_subgroup.relindex_dvd_index_of_le AddSubgroup.relindex_dvd_index_of_le
 
-/- warning: subgroup.relindex_subgroup_of -> Subgroup.relindex_subgroupOf is a dubious translation:
-lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1} {L : Subgroup.{u1} G _inst_1}, (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toHasLe.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (SetLike.partialOrder.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)))) K L) -> (Eq.{1} Nat (Subgroup.relindex.{u1} (coeSort.{succ u1, succ (succ u1)} (Subgroup.{u1} G _inst_1) Type.{u1} (SetLike.hasCoeToSort.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)) L) (Subgroup.toGroup.{u1} G _inst_1 L) (Subgroup.subgroupOf.{u1} G _inst_1 H L) (Subgroup.subgroupOf.{u1} G _inst_1 K L)) (Subgroup.relindex.{u1} G _inst_1 H K))
-but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1} {L : Subgroup.{u1} G _inst_1}, (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toLE.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (CompleteSemilatticeInf.toPartialOrder.{u1} (Subgroup.{u1} G _inst_1) (CompleteLattice.toCompleteSemilatticeInf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instCompleteLatticeSubgroup.{u1} G _inst_1))))) K L) -> (Eq.{1} Nat (Subgroup.relindex.{u1} (Subtype.{succ u1} G (fun (x : G) => Membership.mem.{u1, u1} G (Subgroup.{u1} G _inst_1) (SetLike.instMembership.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.instSetLikeSubgroup.{u1} G _inst_1)) x L)) (Subgroup.toGroup.{u1} G _inst_1 L) (Subgroup.subgroupOf.{u1} G _inst_1 H L) (Subgroup.subgroupOf.{u1} G _inst_1 K L)) (Subgroup.relindex.{u1} G _inst_1 H K))
-Case conversion may be inaccurate. Consider using '#align subgroup.relindex_subgroup_of Subgroup.relindex_subgroupOfₓ'. -/
 @[to_additive]
 theorem relindex_subgroupOf (hKL : K ≤ L) :
     (H.subgroupOf L).relindex (K.subgroupOf L) = H.relindex K :=
@@ -167,12 +137,6 @@ theorem relindex_subgroupOf (hKL : K ≤ L) :
 
 variable (H K L)
 
-/- warning: subgroup.relindex_mul_relindex -> Subgroup.relindex_mul_relindex is a dubious translation:
-lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) (K : Subgroup.{u1} G _inst_1) (L : Subgroup.{u1} G _inst_1), (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toHasLe.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (SetLike.partialOrder.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)))) H K) -> (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toHasLe.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (SetLike.partialOrder.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)))) K L) -> (Eq.{1} Nat (HMul.hMul.{0, 0, 0} Nat Nat Nat (instHMul.{0} Nat Nat.hasMul) (Subgroup.relindex.{u1} G _inst_1 H K) (Subgroup.relindex.{u1} G _inst_1 K L)) (Subgroup.relindex.{u1} G _inst_1 H L))
-but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) (K : Subgroup.{u1} G _inst_1) (L : Subgroup.{u1} G _inst_1), (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toLE.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (CompleteSemilatticeInf.toPartialOrder.{u1} (Subgroup.{u1} G _inst_1) (CompleteLattice.toCompleteSemilatticeInf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instCompleteLatticeSubgroup.{u1} G _inst_1))))) H K) -> (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toLE.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (CompleteSemilatticeInf.toPartialOrder.{u1} (Subgroup.{u1} G _inst_1) (CompleteLattice.toCompleteSemilatticeInf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instCompleteLatticeSubgroup.{u1} G _inst_1))))) K L) -> (Eq.{1} Nat (HMul.hMul.{0, 0, 0} Nat Nat Nat (instHMul.{0} Nat instMulNat) (Subgroup.relindex.{u1} G _inst_1 H K) (Subgroup.relindex.{u1} G _inst_1 K L)) (Subgroup.relindex.{u1} G _inst_1 H L))
-Case conversion may be inaccurate. Consider using '#align subgroup.relindex_mul_relindex Subgroup.relindex_mul_relindexₓ'. -/
 @[to_additive relindex_mul_relindex]
 theorem relindex_mul_relindex (hHK : H ≤ K) (hKL : K ≤ L) :
     H.relindex K * K.relindex L = H.relindex L :=
@@ -182,36 +146,18 @@ theorem relindex_mul_relindex (hHK : H ≤ K) (hKL : K ≤ L) :
 #align subgroup.relindex_mul_relindex Subgroup.relindex_mul_relindex
 #align add_subgroup.relindex_mul_relindex AddSubgroup.relindex_mul_relindex
 
-/- warning: subgroup.inf_relindex_right -> Subgroup.inf_relindex_right is a dubious translation:
-lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) (K : Subgroup.{u1} G _inst_1), Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 (Inf.inf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.hasInf.{u1} G _inst_1) H K) K) (Subgroup.relindex.{u1} G _inst_1 H K)
-but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) (K : Subgroup.{u1} G _inst_1), Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 (Inf.inf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instInfSubgroup.{u1} G _inst_1) H K) K) (Subgroup.relindex.{u1} G _inst_1 H K)
-Case conversion may be inaccurate. Consider using '#align subgroup.inf_relindex_right Subgroup.inf_relindex_rightₓ'. -/
 @[to_additive]
 theorem inf_relindex_right : (H ⊓ K).relindex K = H.relindex K := by
   rw [relindex, relindex, inf_subgroup_of_right]
 #align subgroup.inf_relindex_right Subgroup.inf_relindex_right
 #align add_subgroup.inf_relindex_right AddSubgroup.inf_relindex_right
 
-/- warning: subgroup.inf_relindex_left -> Subgroup.inf_relindex_left is a dubious translation:
-lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) (K : Subgroup.{u1} G _inst_1), Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 (Inf.inf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.hasInf.{u1} G _inst_1) H K) H) (Subgroup.relindex.{u1} G _inst_1 K H)
-but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) (K : Subgroup.{u1} G _inst_1), Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 (Inf.inf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instInfSubgroup.{u1} G _inst_1) H K) H) (Subgroup.relindex.{u1} G _inst_1 K H)
-Case conversion may be inaccurate. Consider using '#align subgroup.inf_relindex_left Subgroup.inf_relindex_leftₓ'. -/
 @[to_additive]
 theorem inf_relindex_left : (H ⊓ K).relindex H = K.relindex H := by
   rw [inf_comm, inf_relindex_right]
 #align subgroup.inf_relindex_left Subgroup.inf_relindex_left
 #align add_subgroup.inf_relindex_left AddSubgroup.inf_relindex_left
 
-/- warning: subgroup.relindex_inf_mul_relindex -> Subgroup.relindex_inf_mul_relindex is a dubious translation:
-lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) (K : Subgroup.{u1} G _inst_1) (L : Subgroup.{u1} G _inst_1), Eq.{1} Nat (HMul.hMul.{0, 0, 0} Nat Nat Nat (instHMul.{0} Nat Nat.hasMul) (Subgroup.relindex.{u1} G _inst_1 H (Inf.inf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.hasInf.{u1} G _inst_1) K L)) (Subgroup.relindex.{u1} G _inst_1 K L)) (Subgroup.relindex.{u1} G _inst_1 (Inf.inf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.hasInf.{u1} G _inst_1) H K) L)
-but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) (K : Subgroup.{u1} G _inst_1) (L : Subgroup.{u1} G _inst_1), Eq.{1} Nat (HMul.hMul.{0, 0, 0} Nat Nat Nat (instHMul.{0} Nat instMulNat) (Subgroup.relindex.{u1} G _inst_1 H (Inf.inf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instInfSubgroup.{u1} G _inst_1) K L)) (Subgroup.relindex.{u1} G _inst_1 K L)) (Subgroup.relindex.{u1} G _inst_1 (Inf.inf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instInfSubgroup.{u1} G _inst_1) H K) L)
-Case conversion may be inaccurate. Consider using '#align subgroup.relindex_inf_mul_relindex Subgroup.relindex_inf_mul_relindexₓ'. -/
 @[to_additive relindex_inf_mul_relindex]
 theorem relindex_inf_mul_relindex : H.relindex (K ⊓ L) * K.relindex L = (H ⊓ K).relindex L := by
   rw [← inf_relindex_right H (K ⊓ L), ← inf_relindex_right K L, ← inf_relindex_right (H ⊓ K) L,
@@ -219,24 +165,12 @@ theorem relindex_inf_mul_relindex : H.relindex (K ⊓ L) * K.relindex L = (H ⊓
 #align subgroup.relindex_inf_mul_relindex Subgroup.relindex_inf_mul_relindex
 #align add_subgroup.relindex_inf_mul_relindex AddSubgroup.relindex_inf_mul_relindex
 
-/- warning: subgroup.relindex_sup_right -> Subgroup.relindex_sup_right is a dubious translation:
-lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) (K : Subgroup.{u1} G _inst_1) [_inst_2 : Subgroup.Normal.{u1} G _inst_1 K], Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 K (Sup.sup.{u1} (Subgroup.{u1} G _inst_1) (SemilatticeSup.toHasSup.{u1} (Subgroup.{u1} G _inst_1) (Lattice.toSemilatticeSup.{u1} (Subgroup.{u1} G _inst_1) (ConditionallyCompleteLattice.toLattice.{u1} (Subgroup.{u1} G _inst_1) (CompleteLattice.toConditionallyCompleteLattice.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.completeLattice.{u1} G _inst_1))))) H K)) (Subgroup.relindex.{u1} G _inst_1 K H)
-but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) (K : Subgroup.{u1} G _inst_1) [_inst_2 : Subgroup.Normal.{u1} G _inst_1 K], Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 K (Sup.sup.{u1} (Subgroup.{u1} G _inst_1) (SemilatticeSup.toSup.{u1} (Subgroup.{u1} G _inst_1) (Lattice.toSemilatticeSup.{u1} (Subgroup.{u1} G _inst_1) (ConditionallyCompleteLattice.toLattice.{u1} (Subgroup.{u1} G _inst_1) (CompleteLattice.toConditionallyCompleteLattice.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instCompleteLatticeSubgroup.{u1} G _inst_1))))) H K)) (Subgroup.relindex.{u1} G _inst_1 K H)
-Case conversion may be inaccurate. Consider using '#align subgroup.relindex_sup_right Subgroup.relindex_sup_rightₓ'. -/
 @[simp, to_additive]
 theorem relindex_sup_right [K.Normal] : K.relindex (H ⊔ K) = K.relindex H :=
   Nat.card_congr (QuotientGroup.quotientInfEquivProdNormalQuotient H K).toEquiv.symm
 #align subgroup.relindex_sup_right Subgroup.relindex_sup_right
 #align add_subgroup.relindex_sup_right AddSubgroup.relindex_sup_right
 
-/- warning: subgroup.relindex_sup_left -> Subgroup.relindex_sup_left is a dubious translation:
-lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) (K : Subgroup.{u1} G _inst_1) [_inst_2 : Subgroup.Normal.{u1} G _inst_1 K], Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 K (Sup.sup.{u1} (Subgroup.{u1} G _inst_1) (SemilatticeSup.toHasSup.{u1} (Subgroup.{u1} G _inst_1) (Lattice.toSemilatticeSup.{u1} (Subgroup.{u1} G _inst_1) (ConditionallyCompleteLattice.toLattice.{u1} (Subgroup.{u1} G _inst_1) (CompleteLattice.toConditionallyCompleteLattice.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.completeLattice.{u1} G _inst_1))))) K H)) (Subgroup.relindex.{u1} G _inst_1 K H)
-but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) (K : Subgroup.{u1} G _inst_1) [_inst_2 : Subgroup.Normal.{u1} G _inst_1 K], Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 K (Sup.sup.{u1} (Subgroup.{u1} G _inst_1) (SemilatticeSup.toSup.{u1} (Subgroup.{u1} G _inst_1) (Lattice.toSemilatticeSup.{u1} (Subgroup.{u1} G _inst_1) (ConditionallyCompleteLattice.toLattice.{u1} (Subgroup.{u1} G _inst_1) (CompleteLattice.toConditionallyCompleteLattice.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instCompleteLatticeSubgroup.{u1} G _inst_1))))) K H)) (Subgroup.relindex.{u1} G _inst_1 K H)
-Case conversion may be inaccurate. Consider using '#align subgroup.relindex_sup_left Subgroup.relindex_sup_leftₓ'. -/
 @[simp, to_additive]
 theorem relindex_sup_left [K.Normal] : K.relindex (K ⊔ H) = K.relindex H := by
   rw [sup_comm, relindex_sup_right]
@@ -253,24 +187,12 @@ theorem relindex_dvd_index_of_normal [H.Normal] : H.relindex K ∣ H.index :=
 
 variable {H K}
 
-/- warning: subgroup.relindex_dvd_of_le_left -> Subgroup.relindex_dvd_of_le_left is a dubious translation:
-lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1} (L : Subgroup.{u1} G _inst_1), (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toHasLe.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (SetLike.partialOrder.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)))) H K) -> (Dvd.Dvd.{0} Nat Nat.hasDvd (Subgroup.relindex.{u1} G _inst_1 K L) (Subgroup.relindex.{u1} G _inst_1 H L))
-but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1} (L : Subgroup.{u1} G _inst_1), (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toLE.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (CompleteSemilatticeInf.toPartialOrder.{u1} (Subgroup.{u1} G _inst_1) (CompleteLattice.toCompleteSemilatticeInf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instCompleteLatticeSubgroup.{u1} G _inst_1))))) H K) -> (Dvd.dvd.{0} Nat Nat.instDvdNat (Subgroup.relindex.{u1} G _inst_1 K L) (Subgroup.relindex.{u1} G _inst_1 H L))
-Case conversion may be inaccurate. Consider using '#align subgroup.relindex_dvd_of_le_left Subgroup.relindex_dvd_of_le_leftₓ'. -/
 @[to_additive]
 theorem relindex_dvd_of_le_left (hHK : H ≤ K) : K.relindex L ∣ H.relindex L :=
   inf_of_le_left hHK ▸ dvd_of_mul_left_eq _ (relindex_inf_mul_relindex _ _ _)
 #align subgroup.relindex_dvd_of_le_left Subgroup.relindex_dvd_of_le_left
 #align add_subgroup.relindex_dvd_of_le_left AddSubgroup.relindex_dvd_of_le_left
 
-/- warning: subgroup.index_eq_two_iff -> Subgroup.index_eq_two_iff is a dubious translation:
-lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1}, Iff (Eq.{1} Nat (Subgroup.index.{u1} G _inst_1 H) (OfNat.ofNat.{0} Nat 2 (OfNat.mk.{0} Nat 2 (bit0.{0} Nat Nat.hasAdd (One.one.{0} Nat Nat.hasOne))))) (Exists.{succ u1} G (fun (a : G) => forall (b : G), Xor' (Membership.Mem.{u1, u1} G (Subgroup.{u1} G _inst_1) (SetLike.hasMem.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)) (HMul.hMul.{u1, u1, u1} G G G (instHMul.{u1} G (MulOneClass.toHasMul.{u1} G (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))))) b a) H) (Membership.Mem.{u1, u1} G (Subgroup.{u1} G _inst_1) (SetLike.hasMem.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)) b H)))
-but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1}, Iff (Eq.{1} Nat (Subgroup.index.{u1} G _inst_1 H) (OfNat.ofNat.{0} Nat 2 (instOfNatNat 2))) (Exists.{succ u1} G (fun (a : G) => forall (b : G), Xor' (Membership.mem.{u1, u1} G (Subgroup.{u1} G _inst_1) (SetLike.instMembership.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.instSetLikeSubgroup.{u1} G _inst_1)) (HMul.hMul.{u1, u1, u1} G G G (instHMul.{u1} G (MulOneClass.toMul.{u1} G (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))))) b a) H) (Membership.mem.{u1, u1} G (Subgroup.{u1} G _inst_1) (SetLike.instMembership.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.instSetLikeSubgroup.{u1} G _inst_1)) b H)))
-Case conversion may be inaccurate. Consider using '#align subgroup.index_eq_two_iff Subgroup.index_eq_two_iffₓ'. -/
 /-- A subgroup has index two if and only if there exists `a` such that for all `b`, exactly one
 of `b * a` and `b` belong to `H`. -/
 @[to_additive
@@ -289,12 +211,6 @@ theorem index_eq_two_iff : H.index = 2 ↔ ∃ a, ∀ b, Xor' (b * a ∈ H) (b 
 #align subgroup.index_eq_two_iff Subgroup.index_eq_two_iff
 #align add_subgroup.index_eq_two_iff AddSubgroup.index_eq_two_iff
 
-/- warning: subgroup.mul_mem_iff_of_index_two -> Subgroup.mul_mem_iff_of_index_two is a dubious translation:
-lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1}, (Eq.{1} Nat (Subgroup.index.{u1} G _inst_1 H) (OfNat.ofNat.{0} Nat 2 (OfNat.mk.{0} Nat 2 (bit0.{0} Nat Nat.hasAdd (One.one.{0} Nat Nat.hasOne))))) -> (forall {a : G} {b : G}, Iff (Membership.Mem.{u1, u1} G (Subgroup.{u1} G _inst_1) (SetLike.hasMem.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)) (HMul.hMul.{u1, u1, u1} G G G (instHMul.{u1} G (MulOneClass.toHasMul.{u1} G (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))))) a b) H) (Iff (Membership.Mem.{u1, u1} G (Subgroup.{u1} G _inst_1) (SetLike.hasMem.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)) a H) (Membership.Mem.{u1, u1} G (Subgroup.{u1} G _inst_1) (SetLike.hasMem.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)) b H)))
-but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1}, (Eq.{1} Nat (Subgroup.index.{u1} G _inst_1 H) (OfNat.ofNat.{0} Nat 2 (instOfNatNat 2))) -> (forall {a : G} {b : G}, Iff (Membership.mem.{u1, u1} G (Subgroup.{u1} G _inst_1) (SetLike.instMembership.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.instSetLikeSubgroup.{u1} G _inst_1)) (HMul.hMul.{u1, u1, u1} G G G (instHMul.{u1} G (MulOneClass.toMul.{u1} G (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))))) a b) H) (Iff (Membership.mem.{u1, u1} G (Subgroup.{u1} G _inst_1) (SetLike.instMembership.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.instSetLikeSubgroup.{u1} G _inst_1)) a H) (Membership.mem.{u1, u1} G (Subgroup.{u1} G _inst_1) (SetLike.instMembership.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.instSetLikeSubgroup.{u1} G _inst_1)) b H)))
-Case conversion may be inaccurate. Consider using '#align subgroup.mul_mem_iff_of_index_two Subgroup.mul_mem_iff_of_index_twoₓ'. -/
 @[to_additive]
 theorem mul_mem_iff_of_index_two (h : H.index = 2) {a b : G} : a * b ∈ H ↔ (a ∈ H ↔ b ∈ H) :=
   by
@@ -307,24 +223,12 @@ theorem mul_mem_iff_of_index_two (h : H.index = 2) {a b : G} : a * b ∈ H ↔ (
 #align subgroup.mul_mem_iff_of_index_two Subgroup.mul_mem_iff_of_index_two
 #align add_subgroup.add_mem_iff_of_index_two AddSubgroup.add_mem_iff_of_index_two
 
-/- warning: subgroup.mul_self_mem_of_index_two -> Subgroup.mul_self_mem_of_index_two is a dubious translation:
-lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1}, (Eq.{1} Nat (Subgroup.index.{u1} G _inst_1 H) (OfNat.ofNat.{0} Nat 2 (OfNat.mk.{0} Nat 2 (bit0.{0} Nat Nat.hasAdd (One.one.{0} Nat Nat.hasOne))))) -> (forall (a : G), Membership.Mem.{u1, u1} G (Subgroup.{u1} G _inst_1) (SetLike.hasMem.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)) (HMul.hMul.{u1, u1, u1} G G G (instHMul.{u1} G (MulOneClass.toHasMul.{u1} G (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))))) a a) H)
-but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1}, (Eq.{1} Nat (Subgroup.index.{u1} G _inst_1 H) (OfNat.ofNat.{0} Nat 2 (instOfNatNat 2))) -> (forall (a : G), Membership.mem.{u1, u1} G (Subgroup.{u1} G _inst_1) (SetLike.instMembership.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.instSetLikeSubgroup.{u1} G _inst_1)) (HMul.hMul.{u1, u1, u1} G G G (instHMul.{u1} G (MulOneClass.toMul.{u1} G (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))))) a a) H)
-Case conversion may be inaccurate. Consider using '#align subgroup.mul_self_mem_of_index_two Subgroup.mul_self_mem_of_index_twoₓ'. -/
 @[to_additive]
 theorem mul_self_mem_of_index_two (h : H.index = 2) (a : G) : a * a ∈ H := by
   rw [mul_mem_iff_of_index_two h]
 #align subgroup.mul_self_mem_of_index_two Subgroup.mul_self_mem_of_index_two
 #align add_subgroup.add_self_mem_of_index_two AddSubgroup.add_self_mem_of_index_two
 
-/- warning: subgroup.sq_mem_of_index_two -> Subgroup.sq_mem_of_index_two is a dubious translation:
-lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1}, (Eq.{1} Nat (Subgroup.index.{u1} G _inst_1 H) (OfNat.ofNat.{0} Nat 2 (OfNat.mk.{0} Nat 2 (bit0.{0} Nat Nat.hasAdd (One.one.{0} Nat Nat.hasOne))))) -> (forall (a : G), Membership.Mem.{u1, u1} G (Subgroup.{u1} G _inst_1) (SetLike.hasMem.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)) (HPow.hPow.{u1, 0, u1} G Nat G (instHPow.{u1, 0} G Nat (Monoid.Pow.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) a (OfNat.ofNat.{0} Nat 2 (OfNat.mk.{0} Nat 2 (bit0.{0} Nat Nat.hasAdd (One.one.{0} Nat Nat.hasOne))))) H)
-but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1}, (Eq.{1} Nat (Subgroup.index.{u1} G _inst_1 H) (OfNat.ofNat.{0} Nat 2 (instOfNatNat 2))) -> (forall (a : G), Membership.mem.{u1, u1} G (Subgroup.{u1} G _inst_1) (SetLike.instMembership.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.instSetLikeSubgroup.{u1} G _inst_1)) (HPow.hPow.{u1, 0, u1} G Nat G (instHPow.{u1, 0} G Nat (Monoid.Pow.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) a (OfNat.ofNat.{0} Nat 2 (instOfNatNat 2))) H)
-Case conversion may be inaccurate. Consider using '#align subgroup.sq_mem_of_index_two Subgroup.sq_mem_of_index_twoₓ'. -/
 @[to_additive two_smul_mem_of_index_two]
 theorem sq_mem_of_index_two (h : H.index = 2) (a : G) : a ^ 2 ∈ H :=
   (pow_two a).symm ▸ mul_self_mem_of_index_two h a
@@ -333,96 +237,48 @@ theorem sq_mem_of_index_two (h : H.index = 2) (a : G) : a ^ 2 ∈ H :=
 
 variable (H K)
 
-/- warning: subgroup.index_top -> Subgroup.index_top is a dubious translation:
-lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G], Eq.{1} Nat (Subgroup.index.{u1} G _inst_1 (Top.top.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.hasTop.{u1} G _inst_1))) (OfNat.ofNat.{0} Nat 1 (OfNat.mk.{0} Nat 1 (One.one.{0} Nat Nat.hasOne)))
-but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G], Eq.{1} Nat (Subgroup.index.{u1} G _inst_1 (Top.top.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instTopSubgroup.{u1} G _inst_1))) (OfNat.ofNat.{0} Nat 1 (instOfNatNat 1))
-Case conversion may be inaccurate. Consider using '#align subgroup.index_top Subgroup.index_topₓ'. -/
 @[simp, to_additive]
 theorem index_top : (⊤ : Subgroup G).index = 1 :=
   Cardinal.toNat_eq_one_iff_unique.mpr ⟨QuotientGroup.subsingleton_quotient_top, ⟨1⟩⟩
 #align subgroup.index_top Subgroup.index_top
 #align add_subgroup.index_top AddSubgroup.index_top
 
-/- warning: subgroup.index_bot -> Subgroup.index_bot is a dubious translation:
-lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G], Eq.{1} Nat (Subgroup.index.{u1} G _inst_1 (Bot.bot.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.hasBot.{u1} G _inst_1))) (Nat.card.{u1} G)
-but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G], Eq.{1} Nat (Subgroup.index.{u1} G _inst_1 (Bot.bot.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instBotSubgroup.{u1} G _inst_1))) (Nat.card.{u1} G)
-Case conversion may be inaccurate. Consider using '#align subgroup.index_bot Subgroup.index_botₓ'. -/
 @[simp, to_additive]
 theorem index_bot : (⊥ : Subgroup G).index = Nat.card G :=
   Cardinal.toNat_congr QuotientGroup.quotientBot.toEquiv
 #align subgroup.index_bot Subgroup.index_bot
 #align add_subgroup.index_bot AddSubgroup.index_bot
 
-/- warning: subgroup.index_bot_eq_card -> Subgroup.index_bot_eq_card is a dubious translation:
-lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] [_inst_2 : Fintype.{u1} G], Eq.{1} Nat (Subgroup.index.{u1} G _inst_1 (Bot.bot.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.hasBot.{u1} G _inst_1))) (Fintype.card.{u1} G _inst_2)
-but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] [_inst_2 : Fintype.{u1} G], Eq.{1} Nat (Subgroup.index.{u1} G _inst_1 (Bot.bot.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instBotSubgroup.{u1} G _inst_1))) (Fintype.card.{u1} G _inst_2)
-Case conversion may be inaccurate. Consider using '#align subgroup.index_bot_eq_card Subgroup.index_bot_eq_cardₓ'. -/
 @[to_additive]
 theorem index_bot_eq_card [Fintype G] : (⊥ : Subgroup G).index = Fintype.card G :=
   index_bot.trans Nat.card_eq_fintype_card
 #align subgroup.index_bot_eq_card Subgroup.index_bot_eq_card
 #align add_subgroup.index_bot_eq_card AddSubgroup.index_bot_eq_card
 
-/- warning: subgroup.relindex_top_left -> Subgroup.relindex_top_left is a dubious translation:
-lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1), Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 (Top.top.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.hasTop.{u1} G _inst_1)) H) (OfNat.ofNat.{0} Nat 1 (OfNat.mk.{0} Nat 1 (One.one.{0} Nat Nat.hasOne)))
-but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1), Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 (Top.top.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instTopSubgroup.{u1} G _inst_1)) H) (OfNat.ofNat.{0} Nat 1 (instOfNatNat 1))
-Case conversion may be inaccurate. Consider using '#align subgroup.relindex_top_left Subgroup.relindex_top_leftₓ'. -/
 @[simp, to_additive]
 theorem relindex_top_left : (⊤ : Subgroup G).relindex H = 1 :=
   index_top
 #align subgroup.relindex_top_left Subgroup.relindex_top_left
 #align add_subgroup.relindex_top_left AddSubgroup.relindex_top_left
 
-/- warning: subgroup.relindex_top_right -> Subgroup.relindex_top_right is a dubious translation:
-lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1), Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 H (Top.top.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.hasTop.{u1} G _inst_1))) (Subgroup.index.{u1} G _inst_1 H)
-but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1), Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 H (Top.top.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instTopSubgroup.{u1} G _inst_1))) (Subgroup.index.{u1} G _inst_1 H)
-Case conversion may be inaccurate. Consider using '#align subgroup.relindex_top_right Subgroup.relindex_top_rightₓ'. -/
 @[simp, to_additive]
 theorem relindex_top_right : H.relindex ⊤ = H.index := by
   rw [← relindex_mul_index (show H ≤ ⊤ from le_top), index_top, mul_one]
 #align subgroup.relindex_top_right Subgroup.relindex_top_right
 #align add_subgroup.relindex_top_right AddSubgroup.relindex_top_right
 
-/- warning: subgroup.relindex_bot_left -> Subgroup.relindex_bot_left is a dubious translation:
-lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1), Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 (Bot.bot.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.hasBot.{u1} G _inst_1)) H) (Nat.card.{u1} (coeSort.{succ u1, succ (succ u1)} (Subgroup.{u1} G _inst_1) Type.{u1} (SetLike.hasCoeToSort.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)) H))
-but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1), Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 (Bot.bot.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instBotSubgroup.{u1} G _inst_1)) H) (Nat.card.{u1} (Subtype.{succ u1} G (fun (x : G) => Membership.mem.{u1, u1} G (Subgroup.{u1} G _inst_1) (SetLike.instMembership.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.instSetLikeSubgroup.{u1} G _inst_1)) x H)))
-Case conversion may be inaccurate. Consider using '#align subgroup.relindex_bot_left Subgroup.relindex_bot_leftₓ'. -/
 @[simp, to_additive]
 theorem relindex_bot_left : (⊥ : Subgroup G).relindex H = Nat.card H := by
   rw [relindex, bot_subgroup_of, index_bot]
 #align subgroup.relindex_bot_left Subgroup.relindex_bot_left
 #align add_subgroup.relindex_bot_left AddSubgroup.relindex_bot_left
 
-/- warning: subgroup.relindex_bot_left_eq_card -> Subgroup.relindex_bot_left_eq_card is a dubious translation:
-lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) [_inst_2 : Fintype.{u1} (coeSort.{succ u1, succ (succ u1)} (Subgroup.{u1} G _inst_1) Type.{u1} (SetLike.hasCoeToSort.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)) H)], Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 (Bot.bot.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.hasBot.{u1} G _inst_1)) H) (Fintype.card.{u1} (coeSort.{succ u1, succ (succ u1)} (Subgroup.{u1} G _inst_1) Type.{u1} (SetLike.hasCoeToSort.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)) H) _inst_2)
-but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) [_inst_2 : Fintype.{u1} (Subtype.{succ u1} G (fun (x : G) => Membership.mem.{u1, u1} G (Subgroup.{u1} G _inst_1) (SetLike.instMembership.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.instSetLikeSubgroup.{u1} G _inst_1)) x H))], Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 (Bot.bot.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instBotSubgroup.{u1} G _inst_1)) H) (Fintype.card.{u1} (Subtype.{succ u1} G (fun (x : G) => Membership.mem.{u1, u1} G (Subgroup.{u1} G _inst_1) (SetLike.instMembership.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.instSetLikeSubgroup.{u1} G _inst_1)) x H)) _inst_2)
-Case conversion may be inaccurate. Consider using '#align subgroup.relindex_bot_left_eq_card Subgroup.relindex_bot_left_eq_cardₓ'. -/
 @[to_additive]
 theorem relindex_bot_left_eq_card [Fintype H] : (⊥ : Subgroup G).relindex H = Fintype.card H :=
   H.relindex_bot_left.trans Nat.card_eq_fintype_card
 #align subgroup.relindex_bot_left_eq_card Subgroup.relindex_bot_left_eq_card
 #align add_subgroup.relindex_bot_left_eq_card AddSubgroup.relindex_bot_left_eq_card
 
-/- warning: subgroup.relindex_bot_right -> Subgroup.relindex_bot_right is a dubious translation:
-lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1), Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 H (Bot.bot.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.hasBot.{u1} G _inst_1))) (OfNat.ofNat.{0} Nat 1 (OfNat.mk.{0} Nat 1 (One.one.{0} Nat Nat.hasOne)))
-but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1), Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 H (Bot.bot.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instBotSubgroup.{u1} G _inst_1))) (OfNat.ofNat.{0} Nat 1 (instOfNatNat 1))
-Case conversion may be inaccurate. Consider using '#align subgroup.relindex_bot_right Subgroup.relindex_bot_rightₓ'. -/
 @[simp, to_additive]
 theorem relindex_bot_right : H.relindex ⊥ = 1 := by rw [relindex, subgroup_of_bot_eq_top, index_top]
 #align subgroup.relindex_bot_right Subgroup.relindex_bot_right
@@ -435,24 +291,12 @@ theorem relindex_self : H.relindex H = 1 := by rw [relindex, subgroup_of_self, i
 #align add_subgroup.relindex_self AddSubgroup.relindex_self
 -/
 
-/- warning: subgroup.index_ker -> Subgroup.index_ker is a dubious translation:
-lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Type.{u2}} [_inst_2 : Group.{u2} H] (f : MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))), Eq.{1} Nat (Subgroup.index.{u1} G _inst_1 (MonoidHom.ker.{u1, u2} G _inst_1 H (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2))) f)) (Nat.card.{u2} (coeSort.{succ u2, succ (succ u2)} (Set.{u2} H) Type.{u2} (Set.hasCoeToSort.{u2} H) (Set.range.{u2, succ u1} H G (coeFn.{max (succ u2) (succ u1), max (succ u1) (succ u2)} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) (fun (_x : MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) => G -> H) (MonoidHom.hasCoeToFun.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) f))))
-but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Type.{u2}} [_inst_2 : Group.{u2} H] (f : MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))), Eq.{1} Nat (Subgroup.index.{u1} G _inst_1 (MonoidHom.ker.{u1, u2} G _inst_1 H (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2))) f)) (Nat.card.{u2} (Set.Elem.{u2} H (Set.range.{u2, succ u1} H G (FunLike.coe.{max (succ u1) (succ u2), succ u1, succ u2} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) G (fun (_x : G) => (fun (x._@.Mathlib.Algebra.Hom.Group._hyg.2397 : G) => H) _x) (MulHomClass.toFunLike.{max u1 u2, u1, u2} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) G H (MulOneClass.toMul.{u1} G (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) (MulOneClass.toMul.{u2} H (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) (MonoidHomClass.toMulHomClass.{max u1 u2, u1, u2} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2))) (MonoidHom.monoidHomClass.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))))) f))))
-Case conversion may be inaccurate. Consider using '#align subgroup.index_ker Subgroup.index_kerₓ'. -/
 @[to_additive]
 theorem index_ker {H} [Group H] (f : G →* H) : f.ker.index = Nat.card (Set.range f) := by
   rw [← MonoidHom.comap_bot, index_comap, relindex_bot_left]; rfl
 #align subgroup.index_ker Subgroup.index_ker
 #align add_subgroup.index_ker AddSubgroup.index_ker
 
-/- warning: subgroup.relindex_ker -> Subgroup.relindex_ker is a dubious translation:
-lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Type.{u2}} [_inst_2 : Group.{u2} H] (f : MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) (K : Subgroup.{u1} G _inst_1), Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 (MonoidHom.ker.{u1, u2} G _inst_1 H (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2))) f) K) (Nat.card.{u2} (coeSort.{succ u2, succ (succ u2)} (Set.{u2} H) Type.{u2} (Set.hasCoeToSort.{u2} H) (Set.image.{u1, u2} G H (coeFn.{max (succ u2) (succ u1), max (succ u1) (succ u2)} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) (fun (_x : MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) => G -> H) (MonoidHom.hasCoeToFun.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) f) ((fun (a : Type.{u1}) (b : Type.{u1}) [self : HasLiftT.{succ u1, succ u1} a b] => self.0) (Subgroup.{u1} G _inst_1) (Set.{u1} G) (HasLiftT.mk.{succ u1, succ u1} (Subgroup.{u1} G _inst_1) (Set.{u1} G) (CoeTCₓ.coe.{succ u1, succ u1} (Subgroup.{u1} G _inst_1) (Set.{u1} G) (SetLike.Set.hasCoeT.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)))) K))))
-but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Type.{u2}} [_inst_2 : Group.{u2} H] (f : MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) (K : Subgroup.{u1} G _inst_1), Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 (MonoidHom.ker.{u1, u2} G _inst_1 H (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2))) f) K) (Nat.card.{u2} (Set.Elem.{u2} H (Set.image.{u1, u2} G H (FunLike.coe.{max (succ u1) (succ u2), succ u1, succ u2} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) G (fun (_x : G) => (fun (x._@.Mathlib.Algebra.Hom.Group._hyg.2397 : G) => H) _x) (MulHomClass.toFunLike.{max u1 u2, u1, u2} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) G H (MulOneClass.toMul.{u1} G (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) (MulOneClass.toMul.{u2} H (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) (MonoidHomClass.toMulHomClass.{max u1 u2, u1, u2} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2))) (MonoidHom.monoidHomClass.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))))) f) (SetLike.coe.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.instSetLikeSubgroup.{u1} G _inst_1) K))))
-Case conversion may be inaccurate. Consider using '#align subgroup.relindex_ker Subgroup.relindex_kerₓ'. -/
 @[to_additive]
 theorem relindex_ker {H} [Group H] (f : G →* H) (K : Subgroup G) :
     f.ker.relindex K = Nat.card (f '' K) := by
@@ -460,24 +304,12 @@ theorem relindex_ker {H} [Group H] (f : G →* H) (K : Subgroup G) :
 #align subgroup.relindex_ker Subgroup.relindex_ker
 #align add_subgroup.relindex_ker AddSubgroup.relindex_ker
 
-/- warning: subgroup.card_mul_index -> Subgroup.card_mul_index is a dubious translation:
-lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1), Eq.{1} Nat (HMul.hMul.{0, 0, 0} Nat Nat Nat (instHMul.{0} Nat Nat.hasMul) (Nat.card.{u1} (coeSort.{succ u1, succ (succ u1)} (Subgroup.{u1} G _inst_1) Type.{u1} (SetLike.hasCoeToSort.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)) H)) (Subgroup.index.{u1} G _inst_1 H)) (Nat.card.{u1} G)
-but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1), Eq.{1} Nat (HMul.hMul.{0, 0, 0} Nat Nat Nat (instHMul.{0} Nat instMulNat) (Nat.card.{u1} (Subtype.{succ u1} G (fun (x : G) => Membership.mem.{u1, u1} G (Subgroup.{u1} G _inst_1) (SetLike.instMembership.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.instSetLikeSubgroup.{u1} G _inst_1)) x H))) (Subgroup.index.{u1} G _inst_1 H)) (Nat.card.{u1} G)
-Case conversion may be inaccurate. Consider using '#align subgroup.card_mul_index Subgroup.card_mul_indexₓ'. -/
 @[simp, to_additive card_mul_index]
 theorem card_mul_index : Nat.card H * H.index = Nat.card G := by
   rw [← relindex_bot_left, ← index_bot]; exact relindex_mul_index bot_le
 #align subgroup.card_mul_index Subgroup.card_mul_index
 #align add_subgroup.card_mul_index AddSubgroup.card_mul_index
 
-/- warning: subgroup.nat_card_dvd_of_injective -> Subgroup.nat_card_dvd_of_injective is a dubious translation:
-lean 3 declaration is
-  forall {G : Type.{u1}} {H : Type.{u2}} [_inst_2 : Group.{u1} G] [_inst_3 : Group.{u2} H] (f : MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_2))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_3)))), (Function.Injective.{succ u1, succ u2} G H (coeFn.{max (succ u2) (succ u1), max (succ u1) (succ u2)} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_2))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_3)))) (fun (_x : MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_2))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_3)))) => G -> H) (MonoidHom.hasCoeToFun.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_2))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_3)))) f)) -> (Dvd.Dvd.{0} Nat Nat.hasDvd (Nat.card.{u1} G) (Nat.card.{u2} H))
-but is expected to have type
-  forall {G : Type.{u2}} {H : Type.{u1}} [_inst_2 : Group.{u2} G] [_inst_3 : Group.{u1} H] (f : MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))), (Function.Injective.{succ u2, succ u1} G H (FunLike.coe.{max (succ u2) (succ u1), succ u2, succ u1} (MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) G (fun (_x : G) => (fun (x._@.Mathlib.Algebra.Hom.Group._hyg.2397 : G) => H) _x) (MulHomClass.toFunLike.{max u2 u1, u2, u1} (MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) G H (MulOneClass.toMul.{u2} G (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2)))) (MulOneClass.toMul.{u1} H (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) (MonoidHomClass.toMulHomClass.{max u2 u1, u2, u1} (MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3))) (MonoidHom.monoidHomClass.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))))) f)) -> (Dvd.dvd.{0} Nat Nat.instDvdNat (Nat.card.{u2} G) (Nat.card.{u1} H))
-Case conversion may be inaccurate. Consider using '#align subgroup.nat_card_dvd_of_injective Subgroup.nat_card_dvd_of_injectiveₓ'. -/
 @[to_additive]
 theorem nat_card_dvd_of_injective {G H : Type _} [Group G] [Group H] (f : G →* H)
     (hf : Function.Injective f) : Nat.card G ∣ Nat.card H :=
@@ -487,24 +319,12 @@ theorem nat_card_dvd_of_injective {G H : Type _} [Group G] [Group H] (f : G →*
 #align subgroup.nat_card_dvd_of_injective Subgroup.nat_card_dvd_of_injective
 #align add_subgroup.nat_card_dvd_of_injective AddSubgroup.nat_card_dvd_of_injective
 
-/- warning: subgroup.nat_card_dvd_of_le -> Subgroup.nat_card_dvd_of_le is a dubious translation:
-lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) (K : Subgroup.{u1} G _inst_1), (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toHasLe.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (SetLike.partialOrder.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)))) H K) -> (Dvd.Dvd.{0} Nat Nat.hasDvd (Nat.card.{u1} (coeSort.{succ u1, succ (succ u1)} (Subgroup.{u1} G _inst_1) Type.{u1} (SetLike.hasCoeToSort.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)) H)) (Nat.card.{u1} (coeSort.{succ u1, succ (succ u1)} (Subgroup.{u1} G _inst_1) Type.{u1} (SetLike.hasCoeToSort.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)) K)))
-but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) (K : Subgroup.{u1} G _inst_1), (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toLE.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (CompleteSemilatticeInf.toPartialOrder.{u1} (Subgroup.{u1} G _inst_1) (CompleteLattice.toCompleteSemilatticeInf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instCompleteLatticeSubgroup.{u1} G _inst_1))))) H K) -> (Dvd.dvd.{0} Nat Nat.instDvdNat (Nat.card.{u1} (Subtype.{succ u1} G (fun (x : G) => Membership.mem.{u1, u1} G (Subgroup.{u1} G _inst_1) (SetLike.instMembership.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.instSetLikeSubgroup.{u1} G _inst_1)) x H))) (Nat.card.{u1} (Subtype.{succ u1} G (fun (x : G) => Membership.mem.{u1, u1} G (Subgroup.{u1} G _inst_1) (SetLike.instMembership.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.instSetLikeSubgroup.{u1} G _inst_1)) x K))))
-Case conversion may be inaccurate. Consider using '#align subgroup.nat_card_dvd_of_le Subgroup.nat_card_dvd_of_leₓ'. -/
 @[to_additive]
 theorem nat_card_dvd_of_le (hHK : H ≤ K) : Nat.card H ∣ Nat.card K :=
   nat_card_dvd_of_injective (inclusion hHK) (inclusion_injective hHK)
 #align subgroup.nat_card_dvd_of_le Subgroup.nat_card_dvd_of_le
 #align add_subgroup.nat_card_dvd_of_le AddSubgroup.nat_card_dvd_of_le
 
-/- warning: subgroup.nat_card_dvd_of_surjective -> Subgroup.nat_card_dvd_of_surjective is a dubious translation:
-lean 3 declaration is
-  forall {G : Type.{u1}} {H : Type.{u2}} [_inst_2 : Group.{u1} G] [_inst_3 : Group.{u2} H] (f : MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_2))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_3)))), (Function.Surjective.{succ u1, succ u2} G H (coeFn.{max (succ u2) (succ u1), max (succ u1) (succ u2)} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_2))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_3)))) (fun (_x : MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_2))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_3)))) => G -> H) (MonoidHom.hasCoeToFun.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_2))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_3)))) f)) -> (Dvd.Dvd.{0} Nat Nat.hasDvd (Nat.card.{u2} H) (Nat.card.{u1} G))
-but is expected to have type
-  forall {G : Type.{u2}} {H : Type.{u1}} [_inst_2 : Group.{u2} G] [_inst_3 : Group.{u1} H] (f : MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))), (Function.Surjective.{succ u2, succ u1} G H (FunLike.coe.{max (succ u2) (succ u1), succ u2, succ u1} (MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) G (fun (_x : G) => (fun (x._@.Mathlib.Algebra.Hom.Group._hyg.2397 : G) => H) _x) (MulHomClass.toFunLike.{max u2 u1, u2, u1} (MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) G H (MulOneClass.toMul.{u2} G (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2)))) (MulOneClass.toMul.{u1} H (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) (MonoidHomClass.toMulHomClass.{max u2 u1, u2, u1} (MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3))) (MonoidHom.monoidHomClass.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))))) f)) -> (Dvd.dvd.{0} Nat Nat.instDvdNat (Nat.card.{u1} H) (Nat.card.{u2} G))
-Case conversion may be inaccurate. Consider using '#align subgroup.nat_card_dvd_of_surjective Subgroup.nat_card_dvd_of_surjectiveₓ'. -/
 @[to_additive]
 theorem nat_card_dvd_of_surjective {G H : Type _} [Group G] [Group H] (f : G →* H)
     (hf : Function.Surjective f) : Nat.card H ∣ Nat.card G :=
@@ -514,12 +334,6 @@ theorem nat_card_dvd_of_surjective {G H : Type _} [Group G] [Group H] (f : G →
 #align subgroup.nat_card_dvd_of_surjective Subgroup.nat_card_dvd_of_surjective
 #align add_subgroup.nat_card_dvd_of_surjective AddSubgroup.nat_card_dvd_of_surjective
 
-/- warning: subgroup.card_dvd_of_surjective -> Subgroup.card_dvd_of_surjective is a dubious translation:
-lean 3 declaration is
-  forall {G : Type.{u1}} {H : Type.{u2}} [_inst_2 : Group.{u1} G] [_inst_3 : Group.{u2} H] [_inst_4 : Fintype.{u1} G] [_inst_5 : Fintype.{u2} H] (f : MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_2))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_3)))), (Function.Surjective.{succ u1, succ u2} G H (coeFn.{max (succ u2) (succ u1), max (succ u1) (succ u2)} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_2))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_3)))) (fun (_x : MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_2))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_3)))) => G -> H) (MonoidHom.hasCoeToFun.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_2))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_3)))) f)) -> (Dvd.Dvd.{0} Nat Nat.hasDvd (Fintype.card.{u2} H _inst_5) (Fintype.card.{u1} G _inst_4))
-but is expected to have type
-  forall {G : Type.{u2}} {H : Type.{u1}} [_inst_2 : Group.{u2} G] [_inst_3 : Group.{u1} H] [_inst_4 : Fintype.{u2} G] [_inst_5 : Fintype.{u1} H] (f : MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))), (Function.Surjective.{succ u2, succ u1} G H (FunLike.coe.{max (succ u2) (succ u1), succ u2, succ u1} (MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) G (fun (_x : G) => (fun (x._@.Mathlib.Algebra.Hom.Group._hyg.2397 : G) => H) _x) (MulHomClass.toFunLike.{max u2 u1, u2, u1} (MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) G H (MulOneClass.toMul.{u2} G (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2)))) (MulOneClass.toMul.{u1} H (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) (MonoidHomClass.toMulHomClass.{max u2 u1, u2, u1} (MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3))) (MonoidHom.monoidHomClass.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))))) f)) -> (Dvd.dvd.{0} Nat Nat.instDvdNat (Fintype.card.{u1} H _inst_5) (Fintype.card.{u2} G _inst_4))
-Case conversion may be inaccurate. Consider using '#align subgroup.card_dvd_of_surjective Subgroup.card_dvd_of_surjectiveₓ'. -/
 @[to_additive]
 theorem card_dvd_of_surjective {G H : Type _} [Group G] [Group H] [Fintype G] [Fintype H]
     (f : G →* H) (hf : Function.Surjective f) : Fintype.card H ∣ Fintype.card G := by
@@ -527,12 +341,6 @@ theorem card_dvd_of_surjective {G H : Type _} [Group G] [Group H] [Fintype G] [F
 #align subgroup.card_dvd_of_surjective Subgroup.card_dvd_of_surjective
 #align add_subgroup.card_dvd_of_surjective AddSubgroup.card_dvd_of_surjective
 
-/- warning: subgroup.index_map -> Subgroup.index_map is a dubious translation:
-lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) {G' : Type.{u2}} [_inst_2 : Group.{u2} G'] (f : MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))), Eq.{1} Nat (Subgroup.index.{u2} G' _inst_2 (Subgroup.map.{u1, u2} G _inst_1 G' _inst_2 f H)) (HMul.hMul.{0, 0, 0} Nat Nat Nat (instHMul.{0} Nat Nat.hasMul) (Subgroup.index.{u1} G _inst_1 (Sup.sup.{u1} (Subgroup.{u1} G _inst_1) (SemilatticeSup.toHasSup.{u1} (Subgroup.{u1} G _inst_1) (Lattice.toSemilatticeSup.{u1} (Subgroup.{u1} G _inst_1) (ConditionallyCompleteLattice.toLattice.{u1} (Subgroup.{u1} G _inst_1) (CompleteLattice.toConditionallyCompleteLattice.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.completeLattice.{u1} G _inst_1))))) H (MonoidHom.ker.{u1, u2} G _inst_1 G' (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) f))) (Subgroup.index.{u2} G' _inst_2 (MonoidHom.range.{u1, u2} G _inst_1 G' _inst_2 f)))
-but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) {G' : Type.{u2}} [_inst_2 : Group.{u2} G'] (f : MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))), Eq.{1} Nat (Subgroup.index.{u2} G' _inst_2 (Subgroup.map.{u1, u2} G _inst_1 G' _inst_2 f H)) (HMul.hMul.{0, 0, 0} Nat Nat Nat (instHMul.{0} Nat instMulNat) (Subgroup.index.{u1} G _inst_1 (Sup.sup.{u1} (Subgroup.{u1} G _inst_1) (SemilatticeSup.toSup.{u1} (Subgroup.{u1} G _inst_1) (Lattice.toSemilatticeSup.{u1} (Subgroup.{u1} G _inst_1) (ConditionallyCompleteLattice.toLattice.{u1} (Subgroup.{u1} G _inst_1) (CompleteLattice.toConditionallyCompleteLattice.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instCompleteLatticeSubgroup.{u1} G _inst_1))))) H (MonoidHom.ker.{u1, u2} G _inst_1 G' (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) f))) (Subgroup.index.{u2} G' _inst_2 (MonoidHom.range.{u1, u2} G _inst_1 G' _inst_2 f)))
-Case conversion may be inaccurate. Consider using '#align subgroup.index_map Subgroup.index_mapₓ'. -/
 @[to_additive]
 theorem index_map {G' : Type _} [Group G'] (f : G →* G') :
     (H.map f).index = (H ⊔ f.ker).index * f.range.index := by
@@ -540,12 +348,6 @@ theorem index_map {G' : Type _} [Group G'] (f : G →* G') :
 #align subgroup.index_map Subgroup.index_map
 #align add_subgroup.index_map AddSubgroup.index_map
 
-/- warning: subgroup.index_map_dvd -> Subgroup.index_map_dvd is a dubious translation:
-lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) {G' : Type.{u2}} [_inst_2 : Group.{u2} G'] {f : MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))}, (Function.Surjective.{succ u1, succ u2} G G' (coeFn.{max (succ u2) (succ u1), max (succ u1) (succ u2)} (MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) (fun (_x : MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) => G -> G') (MonoidHom.hasCoeToFun.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) f)) -> (Dvd.Dvd.{0} Nat Nat.hasDvd (Subgroup.index.{u2} G' _inst_2 (Subgroup.map.{u1, u2} G _inst_1 G' _inst_2 f H)) (Subgroup.index.{u1} G _inst_1 H))
-but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) {G' : Type.{u2}} [_inst_2 : Group.{u2} G'] {f : MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))}, (Function.Surjective.{succ u1, succ u2} G G' (FunLike.coe.{max (succ u1) (succ u2), succ u1, succ u2} (MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) G (fun (_x : G) => (fun (x._@.Mathlib.Algebra.Hom.Group._hyg.2397 : G) => G') _x) (MulHomClass.toFunLike.{max u1 u2, u1, u2} (MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) G G' (MulOneClass.toMul.{u1} G (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) (MulOneClass.toMul.{u2} G' (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) (MonoidHomClass.toMulHomClass.{max u1 u2, u1, u2} (MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (MonoidHom.monoidHomClass.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))))) f)) -> (Dvd.dvd.{0} Nat Nat.instDvdNat (Subgroup.index.{u2} G' _inst_2 (Subgroup.map.{u1, u2} G _inst_1 G' _inst_2 f H)) (Subgroup.index.{u1} G _inst_1 H))
-Case conversion may be inaccurate. Consider using '#align subgroup.index_map_dvd Subgroup.index_map_dvdₓ'. -/
 @[to_additive]
 theorem index_map_dvd {G' : Type _} [Group G'] {f : G →* G'} (hf : Function.Surjective f) :
     (H.map f).index ∣ H.index :=
@@ -555,12 +357,6 @@ theorem index_map_dvd {G' : Type _} [Group G'] {f : G →* G'} (hf : Function.Su
 #align subgroup.index_map_dvd Subgroup.index_map_dvd
 #align add_subgroup.index_map_dvd AddSubgroup.index_map_dvd
 
-/- warning: subgroup.dvd_index_map -> Subgroup.dvd_index_map is a dubious translation:
-lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) {G' : Type.{u2}} [_inst_2 : Group.{u2} G'] {f : MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))}, (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toHasLe.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (SetLike.partialOrder.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)))) (MonoidHom.ker.{u1, u2} G _inst_1 G' (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) f) H) -> (Dvd.Dvd.{0} Nat Nat.hasDvd (Subgroup.index.{u1} G _inst_1 H) (Subgroup.index.{u2} G' _inst_2 (Subgroup.map.{u1, u2} G _inst_1 G' _inst_2 f H)))
-but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) {G' : Type.{u2}} [_inst_2 : Group.{u2} G'] {f : MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))}, (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toLE.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (CompleteSemilatticeInf.toPartialOrder.{u1} (Subgroup.{u1} G _inst_1) (CompleteLattice.toCompleteSemilatticeInf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instCompleteLatticeSubgroup.{u1} G _inst_1))))) (MonoidHom.ker.{u1, u2} G _inst_1 G' (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) f) H) -> (Dvd.dvd.{0} Nat Nat.instDvdNat (Subgroup.index.{u1} G _inst_1 H) (Subgroup.index.{u2} G' _inst_2 (Subgroup.map.{u1, u2} G _inst_1 G' _inst_2 f H)))
-Case conversion may be inaccurate. Consider using '#align subgroup.dvd_index_map Subgroup.dvd_index_mapₓ'. -/
 @[to_additive]
 theorem dvd_index_map {G' : Type _} [Group G'] {f : G →* G'} (hf : f.ker ≤ H) :
     H.index ∣ (H.map f).index := by
@@ -569,12 +365,6 @@ theorem dvd_index_map {G' : Type _} [Group G'] {f : G →* G'} (hf : f.ker ≤ H
 #align subgroup.dvd_index_map Subgroup.dvd_index_map
 #align add_subgroup.dvd_index_map AddSubgroup.dvd_index_map
 
-/- warning: subgroup.index_map_eq -> Subgroup.index_map_eq is a dubious translation:
-lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) {G' : Type.{u2}} [_inst_2 : Group.{u2} G'] {f : MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))}, (Function.Surjective.{succ u1, succ u2} G G' (coeFn.{max (succ u2) (succ u1), max (succ u1) (succ u2)} (MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) (fun (_x : MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) => G -> G') (MonoidHom.hasCoeToFun.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) f)) -> (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toHasLe.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (SetLike.partialOrder.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)))) (MonoidHom.ker.{u1, u2} G _inst_1 G' (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) f) H) -> (Eq.{1} Nat (Subgroup.index.{u2} G' _inst_2 (Subgroup.map.{u1, u2} G _inst_1 G' _inst_2 f H)) (Subgroup.index.{u1} G _inst_1 H))
-but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) {G' : Type.{u2}} [_inst_2 : Group.{u2} G'] {f : MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))}, (Function.Surjective.{succ u1, succ u2} G G' (FunLike.coe.{max (succ u1) (succ u2), succ u1, succ u2} (MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) G (fun (_x : G) => (fun (x._@.Mathlib.Algebra.Hom.Group._hyg.2397 : G) => G') _x) (MulHomClass.toFunLike.{max u1 u2, u1, u2} (MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) G G' (MulOneClass.toMul.{u1} G (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) (MulOneClass.toMul.{u2} G' (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) (MonoidHomClass.toMulHomClass.{max u1 u2, u1, u2} (MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (MonoidHom.monoidHomClass.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))))) f)) -> (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toLE.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (CompleteSemilatticeInf.toPartialOrder.{u1} (Subgroup.{u1} G _inst_1) (CompleteLattice.toCompleteSemilatticeInf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instCompleteLatticeSubgroup.{u1} G _inst_1))))) (MonoidHom.ker.{u1, u2} G _inst_1 G' (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) f) H) -> (Eq.{1} Nat (Subgroup.index.{u2} G' _inst_2 (Subgroup.map.{u1, u2} G _inst_1 G' _inst_2 f H)) (Subgroup.index.{u1} G _inst_1 H))
-Case conversion may be inaccurate. Consider using '#align subgroup.index_map_eq Subgroup.index_map_eqₓ'. -/
 @[to_additive]
 theorem index_map_eq {G' : Type _} [Group G'] {f : G →* G'} (hf1 : Function.Surjective f)
     (hf2 : f.ker ≤ H) : (H.map f).index = H.index :=
@@ -590,12 +380,6 @@ theorem index_eq_card [Fintype (G ⧸ H)] : H.index = Fintype.card (G ⧸ H) :=
 #align add_subgroup.index_eq_card AddSubgroup.index_eq_card
 -/
 
-/- warning: subgroup.index_mul_card -> Subgroup.index_mul_card is a dubious translation:
-lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) [_inst_2 : Fintype.{u1} G] [hH : Fintype.{u1} (coeSort.{succ u1, succ (succ u1)} (Subgroup.{u1} G _inst_1) Type.{u1} (SetLike.hasCoeToSort.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)) H)], Eq.{1} Nat (HMul.hMul.{0, 0, 0} Nat Nat Nat (instHMul.{0} Nat Nat.hasMul) (Subgroup.index.{u1} G _inst_1 H) (Fintype.card.{u1} (coeSort.{succ u1, succ (succ u1)} (Subgroup.{u1} G _inst_1) Type.{u1} (SetLike.hasCoeToSort.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)) H) hH)) (Fintype.card.{u1} G _inst_2)
-but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) [_inst_2 : Fintype.{u1} G] [hH : Fintype.{u1} (Subtype.{succ u1} G (fun (x : G) => Membership.mem.{u1, u1} G (Subgroup.{u1} G _inst_1) (SetLike.instMembership.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.instSetLikeSubgroup.{u1} G _inst_1)) x H))], Eq.{1} Nat (HMul.hMul.{0, 0, 0} Nat Nat Nat (instHMul.{0} Nat instMulNat) (Subgroup.index.{u1} G _inst_1 H) (Fintype.card.{u1} (Subtype.{succ u1} G (fun (x : G) => Membership.mem.{u1, u1} G (Subgroup.{u1} G _inst_1) (SetLike.instMembership.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.instSetLikeSubgroup.{u1} G _inst_1)) x H)) hH)) (Fintype.card.{u1} G _inst_2)
-Case conversion may be inaccurate. Consider using '#align subgroup.index_mul_card Subgroup.index_mul_cardₓ'. -/
 @[to_additive index_mul_card]
 theorem index_mul_card [Fintype G] [hH : Fintype H] : H.index * Fintype.card H = Fintype.card G :=
   by
@@ -614,24 +398,12 @@ theorem index_dvd_card [Fintype G] : H.index ∣ Fintype.card G := by
 
 variable {H K L}
 
-/- warning: subgroup.relindex_eq_zero_of_le_left -> Subgroup.relindex_eq_zero_of_le_left is a dubious translation:
-lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1} {L : Subgroup.{u1} G _inst_1}, (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toHasLe.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (SetLike.partialOrder.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)))) H K) -> (Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 K L) (OfNat.ofNat.{0} Nat 0 (OfNat.mk.{0} Nat 0 (Zero.zero.{0} Nat Nat.hasZero)))) -> (Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 H L) (OfNat.ofNat.{0} Nat 0 (OfNat.mk.{0} Nat 0 (Zero.zero.{0} Nat Nat.hasZero))))
-but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1} {L : Subgroup.{u1} G _inst_1}, (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toLE.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (CompleteSemilatticeInf.toPartialOrder.{u1} (Subgroup.{u1} G _inst_1) (CompleteLattice.toCompleteSemilatticeInf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instCompleteLatticeSubgroup.{u1} G _inst_1))))) H K) -> (Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 K L) (OfNat.ofNat.{0} Nat 0 (instOfNatNat 0))) -> (Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 H L) (OfNat.ofNat.{0} Nat 0 (instOfNatNat 0)))
-Case conversion may be inaccurate. Consider using '#align subgroup.relindex_eq_zero_of_le_left Subgroup.relindex_eq_zero_of_le_leftₓ'. -/
 @[to_additive]
 theorem relindex_eq_zero_of_le_left (hHK : H ≤ K) (hKL : K.relindex L = 0) : H.relindex L = 0 :=
   eq_zero_of_zero_dvd (hKL ▸ relindex_dvd_of_le_left L hHK)
 #align subgroup.relindex_eq_zero_of_le_left Subgroup.relindex_eq_zero_of_le_left
 #align add_subgroup.relindex_eq_zero_of_le_left AddSubgroup.relindex_eq_zero_of_le_left
 
-/- warning: subgroup.relindex_eq_zero_of_le_right -> Subgroup.relindex_eq_zero_of_le_right is a dubious translation:
-lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1} {L : Subgroup.{u1} G _inst_1}, (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toHasLe.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (SetLike.partialOrder.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)))) K L) -> (Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 H K) (OfNat.ofNat.{0} Nat 0 (OfNat.mk.{0} Nat 0 (Zero.zero.{0} Nat Nat.hasZero)))) -> (Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 H L) (OfNat.ofNat.{0} Nat 0 (OfNat.mk.{0} Nat 0 (Zero.zero.{0} Nat Nat.hasZero))))
-but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1} {L : Subgroup.{u1} G _inst_1}, (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toLE.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (CompleteSemilatticeInf.toPartialOrder.{u1} (Subgroup.{u1} G _inst_1) (CompleteLattice.toCompleteSemilatticeInf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instCompleteLatticeSubgroup.{u1} G _inst_1))))) K L) -> (Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 H K) (OfNat.ofNat.{0} Nat 0 (instOfNatNat 0))) -> (Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 H L) (OfNat.ofNat.{0} Nat 0 (instOfNatNat 0)))
-Case conversion may be inaccurate. Consider using '#align subgroup.relindex_eq_zero_of_le_right Subgroup.relindex_eq_zero_of_le_rightₓ'. -/
 @[to_additive]
 theorem relindex_eq_zero_of_le_right (hKL : K ≤ L) (hHK : H.relindex K = 0) : H.relindex L = 0 :=
   Finite.card_eq_zero_of_embedding (quotientSubgroupOfEmbeddingOfLe H hKL) hHK
@@ -646,12 +418,6 @@ theorem index_eq_zero_of_relindex_eq_zero (h : H.relindex K = 0) : H.index = 0 :
 #align add_subgroup.index_eq_zero_of_relindex_eq_zero AddSubgroup.index_eq_zero_of_relindex_eq_zero
 -/
 
-/- warning: subgroup.relindex_le_of_le_left -> Subgroup.relindex_le_of_le_left is a dubious translation:
-lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1} {L : Subgroup.{u1} G _inst_1}, (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toHasLe.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (SetLike.partialOrder.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)))) H K) -> (Ne.{1} Nat (Subgroup.relindex.{u1} G _inst_1 H L) (OfNat.ofNat.{0} Nat 0 (OfNat.mk.{0} Nat 0 (Zero.zero.{0} Nat Nat.hasZero)))) -> (LE.le.{0} Nat Nat.hasLe (Subgroup.relindex.{u1} G _inst_1 K L) (Subgroup.relindex.{u1} G _inst_1 H L))
-but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1} {L : Subgroup.{u1} G _inst_1}, (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toLE.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (CompleteSemilatticeInf.toPartialOrder.{u1} (Subgroup.{u1} G _inst_1) (CompleteLattice.toCompleteSemilatticeInf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instCompleteLatticeSubgroup.{u1} G _inst_1))))) H K) -> (Ne.{1} Nat (Subgroup.relindex.{u1} G _inst_1 H L) (OfNat.ofNat.{0} Nat 0 (instOfNatNat 0))) -> (LE.le.{0} Nat instLENat (Subgroup.relindex.{u1} G _inst_1 K L) (Subgroup.relindex.{u1} G _inst_1 H L))
-Case conversion may be inaccurate. Consider using '#align subgroup.relindex_le_of_le_left Subgroup.relindex_le_of_le_leftₓ'. -/
 @[to_additive]
 theorem relindex_le_of_le_left (hHK : H ≤ K) (hHL : H.relindex L ≠ 0) :
     K.relindex L ≤ H.relindex L :=
@@ -659,12 +425,6 @@ theorem relindex_le_of_le_left (hHK : H ≤ K) (hHL : H.relindex L ≠ 0) :
 #align subgroup.relindex_le_of_le_left Subgroup.relindex_le_of_le_left
 #align add_subgroup.relindex_le_of_le_left AddSubgroup.relindex_le_of_le_left
 
-/- warning: subgroup.relindex_le_of_le_right -> Subgroup.relindex_le_of_le_right is a dubious translation:
-lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1} {L : Subgroup.{u1} G _inst_1}, (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toHasLe.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (SetLike.partialOrder.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)))) K L) -> (Ne.{1} Nat (Subgroup.relindex.{u1} G _inst_1 H L) (OfNat.ofNat.{0} Nat 0 (OfNat.mk.{0} Nat 0 (Zero.zero.{0} Nat Nat.hasZero)))) -> (LE.le.{0} Nat Nat.hasLe (Subgroup.relindex.{u1} G _inst_1 H K) (Subgroup.relindex.{u1} G _inst_1 H L))
-but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1} {L : Subgroup.{u1} G _inst_1}, (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toLE.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (CompleteSemilatticeInf.toPartialOrder.{u1} (Subgroup.{u1} G _inst_1) (CompleteLattice.toCompleteSemilatticeInf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instCompleteLatticeSubgroup.{u1} G _inst_1))))) K L) -> (Ne.{1} Nat (Subgroup.relindex.{u1} G _inst_1 H L) (OfNat.ofNat.{0} Nat 0 (instOfNatNat 0))) -> (LE.le.{0} Nat instLENat (Subgroup.relindex.{u1} G _inst_1 H K) (Subgroup.relindex.{u1} G _inst_1 H L))
-Case conversion may be inaccurate. Consider using '#align subgroup.relindex_le_of_le_right Subgroup.relindex_le_of_le_rightₓ'. -/
 @[to_additive]
 theorem relindex_le_of_le_right (hKL : K ≤ L) (hHL : H.relindex L ≠ 0) :
     H.relindex K ≤ H.relindex L :=
@@ -682,12 +442,6 @@ theorem relindex_ne_zero_trans (hHK : H.relindex K ≠ 0) (hKL : K.relindex L 
 #align add_subgroup.relindex_ne_zero_trans AddSubgroup.relindex_ne_zero_trans
 -/
 
-/- warning: subgroup.relindex_inf_ne_zero -> Subgroup.relindex_inf_ne_zero is a dubious translation:
-lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1} {L : Subgroup.{u1} G _inst_1}, (Ne.{1} Nat (Subgroup.relindex.{u1} G _inst_1 H L) (OfNat.ofNat.{0} Nat 0 (OfNat.mk.{0} Nat 0 (Zero.zero.{0} Nat Nat.hasZero)))) -> (Ne.{1} Nat (Subgroup.relindex.{u1} G _inst_1 K L) (OfNat.ofNat.{0} Nat 0 (OfNat.mk.{0} Nat 0 (Zero.zero.{0} Nat Nat.hasZero)))) -> (Ne.{1} Nat (Subgroup.relindex.{u1} G _inst_1 (Inf.inf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.hasInf.{u1} G _inst_1) H K) L) (OfNat.ofNat.{0} Nat 0 (OfNat.mk.{0} Nat 0 (Zero.zero.{0} Nat Nat.hasZero))))
-but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1} {L : Subgroup.{u1} G _inst_1}, (Ne.{1} Nat (Subgroup.relindex.{u1} G _inst_1 H L) (OfNat.ofNat.{0} Nat 0 (instOfNatNat 0))) -> (Ne.{1} Nat (Subgroup.relindex.{u1} G _inst_1 K L) (OfNat.ofNat.{0} Nat 0 (instOfNatNat 0))) -> (Ne.{1} Nat (Subgroup.relindex.{u1} G _inst_1 (Inf.inf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instInfSubgroup.{u1} G _inst_1) H K) L) (OfNat.ofNat.{0} Nat 0 (instOfNatNat 0)))
-Case conversion may be inaccurate. Consider using '#align subgroup.relindex_inf_ne_zero Subgroup.relindex_inf_ne_zeroₓ'. -/
 @[to_additive]
 theorem relindex_inf_ne_zero (hH : H.relindex L ≠ 0) (hK : K.relindex L ≠ 0) :
     (H ⊓ K).relindex L ≠ 0 :=
@@ -699,12 +453,6 @@ theorem relindex_inf_ne_zero (hH : H.relindex L ≠ 0) (hK : K.relindex L ≠ 0)
 #align subgroup.relindex_inf_ne_zero Subgroup.relindex_inf_ne_zero
 #align add_subgroup.relindex_inf_ne_zero AddSubgroup.relindex_inf_ne_zero
 
-/- warning: subgroup.index_inf_ne_zero -> Subgroup.index_inf_ne_zero is a dubious translation:
-lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1}, (Ne.{1} Nat (Subgroup.index.{u1} G _inst_1 H) (OfNat.ofNat.{0} Nat 0 (OfNat.mk.{0} Nat 0 (Zero.zero.{0} Nat Nat.hasZero)))) -> (Ne.{1} Nat (Subgroup.index.{u1} G _inst_1 K) (OfNat.ofNat.{0} Nat 0 (OfNat.mk.{0} Nat 0 (Zero.zero.{0} Nat Nat.hasZero)))) -> (Ne.{1} Nat (Subgroup.index.{u1} G _inst_1 (Inf.inf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.hasInf.{u1} G _inst_1) H K)) (OfNat.ofNat.{0} Nat 0 (OfNat.mk.{0} Nat 0 (Zero.zero.{0} Nat Nat.hasZero))))
-but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1}, (Ne.{1} Nat (Subgroup.index.{u1} G _inst_1 H) (OfNat.ofNat.{0} Nat 0 (instOfNatNat 0))) -> (Ne.{1} Nat (Subgroup.index.{u1} G _inst_1 K) (OfNat.ofNat.{0} Nat 0 (instOfNatNat 0))) -> (Ne.{1} Nat (Subgroup.index.{u1} G _inst_1 (Inf.inf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instInfSubgroup.{u1} G _inst_1) H K)) (OfNat.ofNat.{0} Nat 0 (instOfNatNat 0)))
-Case conversion may be inaccurate. Consider using '#align subgroup.index_inf_ne_zero Subgroup.index_inf_ne_zeroₓ'. -/
 @[to_additive]
 theorem index_inf_ne_zero (hH : H.index ≠ 0) (hK : K.index ≠ 0) : (H ⊓ K).index ≠ 0 :=
   by
@@ -713,12 +461,6 @@ theorem index_inf_ne_zero (hH : H.index ≠ 0) (hK : K.index ≠ 0) : (H ⊓ K).
 #align subgroup.index_inf_ne_zero Subgroup.index_inf_ne_zero
 #align add_subgroup.index_inf_ne_zero AddSubgroup.index_inf_ne_zero
 
-/- warning: subgroup.relindex_inf_le -> Subgroup.relindex_inf_le is a dubious translation:
-lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1} {L : Subgroup.{u1} G _inst_1}, LE.le.{0} Nat Nat.hasLe (Subgroup.relindex.{u1} G _inst_1 (Inf.inf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.hasInf.{u1} G _inst_1) H K) L) (HMul.hMul.{0, 0, 0} Nat Nat Nat (instHMul.{0} Nat Nat.hasMul) (Subgroup.relindex.{u1} G _inst_1 H L) (Subgroup.relindex.{u1} G _inst_1 K L))
-but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1} {L : Subgroup.{u1} G _inst_1}, LE.le.{0} Nat instLENat (Subgroup.relindex.{u1} G _inst_1 (Inf.inf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instInfSubgroup.{u1} G _inst_1) H K) L) (HMul.hMul.{0, 0, 0} Nat Nat Nat (instHMul.{0} Nat instMulNat) (Subgroup.relindex.{u1} G _inst_1 H L) (Subgroup.relindex.{u1} G _inst_1 K L))
-Case conversion may be inaccurate. Consider using '#align subgroup.relindex_inf_le Subgroup.relindex_inf_leₓ'. -/
 @[to_additive]
 theorem relindex_inf_le : (H ⊓ K).relindex L ≤ H.relindex L * K.relindex L :=
   by
@@ -730,12 +472,6 @@ theorem relindex_inf_le : (H ⊓ K).relindex L ≤ H.relindex L * K.relindex L :
 #align subgroup.relindex_inf_le Subgroup.relindex_inf_le
 #align add_subgroup.relindex_inf_le AddSubgroup.relindex_inf_le
 
-/- warning: subgroup.index_inf_le -> Subgroup.index_inf_le is a dubious translation:
-lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1}, LE.le.{0} Nat Nat.hasLe (Subgroup.index.{u1} G _inst_1 (Inf.inf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.hasInf.{u1} G _inst_1) H K)) (HMul.hMul.{0, 0, 0} Nat Nat Nat (instHMul.{0} Nat Nat.hasMul) (Subgroup.index.{u1} G _inst_1 H) (Subgroup.index.{u1} G _inst_1 K))
-but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1}, LE.le.{0} Nat instLENat (Subgroup.index.{u1} G _inst_1 (Inf.inf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instInfSubgroup.{u1} G _inst_1) H K)) (HMul.hMul.{0, 0, 0} Nat Nat Nat (instHMul.{0} Nat instMulNat) (Subgroup.index.{u1} G _inst_1 H) (Subgroup.index.{u1} G _inst_1 K))
-Case conversion may be inaccurate. Consider using '#align subgroup.index_inf_le Subgroup.index_inf_leₓ'. -/
 @[to_additive]
 theorem index_inf_le : (H ⊓ K).index ≤ H.index * K.index := by
   simp_rw [← relindex_top_right, relindex_inf_le]
@@ -786,12 +522,6 @@ theorem index_iInf_le {ι : Type _} [Fintype ι] (f : ι → Subgroup G) :
 #align add_subgroup.index_infi_le AddSubgroup.index_iInf_le
 -/
 
-/- warning: subgroup.index_eq_one -> Subgroup.index_eq_one is a dubious translation:
-lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1}, Iff (Eq.{1} Nat (Subgroup.index.{u1} G _inst_1 H) (OfNat.ofNat.{0} Nat 1 (OfNat.mk.{0} Nat 1 (One.one.{0} Nat Nat.hasOne)))) (Eq.{succ u1} (Subgroup.{u1} G _inst_1) H (Top.top.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.hasTop.{u1} G _inst_1)))
-but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1}, Iff (Eq.{1} Nat (Subgroup.index.{u1} G _inst_1 H) (OfNat.ofNat.{0} Nat 1 (instOfNatNat 1))) (Eq.{succ u1} (Subgroup.{u1} G _inst_1) H (Top.top.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instTopSubgroup.{u1} G _inst_1)))
-Case conversion may be inaccurate. Consider using '#align subgroup.index_eq_one Subgroup.index_eq_oneₓ'. -/
 @[simp, to_additive index_eq_one]
 theorem index_eq_one : H.index = 1 ↔ H = ⊤ :=
   ⟨fun h =>
@@ -800,24 +530,12 @@ theorem index_eq_one : H.index = 1 ↔ H = ⊤ :=
 #align subgroup.index_eq_one Subgroup.index_eq_one
 #align add_subgroup.index_eq_one AddSubgroup.index_eq_one
 
-/- warning: subgroup.relindex_eq_one -> Subgroup.relindex_eq_one is a dubious translation:
-lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1}, Iff (Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 H K) (OfNat.ofNat.{0} Nat 1 (OfNat.mk.{0} Nat 1 (One.one.{0} Nat Nat.hasOne)))) (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toHasLe.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (SetLike.partialOrder.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)))) K H)
-but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1}, Iff (Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 H K) (OfNat.ofNat.{0} Nat 1 (instOfNatNat 1))) (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toLE.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (CompleteSemilatticeInf.toPartialOrder.{u1} (Subgroup.{u1} G _inst_1) (CompleteLattice.toCompleteSemilatticeInf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instCompleteLatticeSubgroup.{u1} G _inst_1))))) K H)
-Case conversion may be inaccurate. Consider using '#align subgroup.relindex_eq_one Subgroup.relindex_eq_oneₓ'. -/
 @[simp, to_additive relindex_eq_one]
 theorem relindex_eq_one : H.relindex K = 1 ↔ K ≤ H :=
   index_eq_one.trans subgroupOf_eq_top
 #align subgroup.relindex_eq_one Subgroup.relindex_eq_one
 #align add_subgroup.relindex_eq_one AddSubgroup.relindex_eq_one
 
-/- warning: subgroup.card_eq_one -> Subgroup.card_eq_one is a dubious translation:
-lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1}, Iff (Eq.{1} Nat (Nat.card.{u1} (coeSort.{succ u1, succ (succ u1)} (Subgroup.{u1} G _inst_1) Type.{u1} (SetLike.hasCoeToSort.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)) H)) (OfNat.ofNat.{0} Nat 1 (OfNat.mk.{0} Nat 1 (One.one.{0} Nat Nat.hasOne)))) (Eq.{succ u1} (Subgroup.{u1} G _inst_1) H (Bot.bot.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.hasBot.{u1} G _inst_1)))
-but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1}, Iff (Eq.{1} Nat (Nat.card.{u1} (Subtype.{succ u1} G (fun (x : G) => Membership.mem.{u1, u1} G (Subgroup.{u1} G _inst_1) (SetLike.instMembership.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.instSetLikeSubgroup.{u1} G _inst_1)) x H))) (OfNat.ofNat.{0} Nat 1 (instOfNatNat 1))) (Eq.{succ u1} (Subgroup.{u1} G _inst_1) H (Bot.bot.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instBotSubgroup.{u1} G _inst_1)))
-Case conversion may be inaccurate. Consider using '#align subgroup.card_eq_one Subgroup.card_eq_oneₓ'. -/
 @[simp, to_additive card_eq_one]
 theorem card_eq_one : Nat.card H = 1 ↔ H = ⊥ :=
   H.relindex_bot_left ▸ relindex_eq_one.trans le_bot_iff
@@ -841,12 +559,6 @@ noncomputable def fintypeOfIndexNeZero (hH : H.index ≠ 0) : Fintype (G ⧸ H)
 #align add_subgroup.fintype_of_index_ne_zero AddSubgroup.fintypeOfIndexNeZero
 -/
 
-/- warning: subgroup.one_lt_index_of_ne_top -> Subgroup.one_lt_index_of_ne_top is a dubious translation:
-lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} [_inst_2 : Finite.{succ u1} (HasQuotient.Quotient.{u1, u1} G (Subgroup.{u1} G _inst_1) (QuotientGroup.Subgroup.hasQuotient.{u1} G _inst_1) H)], (Ne.{succ u1} (Subgroup.{u1} G _inst_1) H (Top.top.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.hasTop.{u1} G _inst_1))) -> (LT.lt.{0} Nat Nat.hasLt (OfNat.ofNat.{0} Nat 1 (OfNat.mk.{0} Nat 1 (One.one.{0} Nat Nat.hasOne))) (Subgroup.index.{u1} G _inst_1 H))
-but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} [_inst_2 : Finite.{succ u1} (HasQuotient.Quotient.{u1, u1} G (Subgroup.{u1} G _inst_1) (QuotientGroup.instHasQuotientSubgroup.{u1} G _inst_1) H)], (Ne.{succ u1} (Subgroup.{u1} G _inst_1) H (Top.top.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instTopSubgroup.{u1} G _inst_1))) -> (LT.lt.{0} Nat instLTNat (OfNat.ofNat.{0} Nat 1 (instOfNatNat 1)) (Subgroup.index.{u1} G _inst_1 H))
-Case conversion may be inaccurate. Consider using '#align subgroup.one_lt_index_of_ne_top Subgroup.one_lt_index_of_ne_topₓ'. -/
 @[to_additive one_lt_index_of_ne_top]
 theorem one_lt_index_of_ne_top [Finite (G ⧸ H)] (hH : H ≠ ⊤) : 1 < H.index :=
   Nat.one_lt_iff_ne_zero_and_ne_one.mpr ⟨index_ne_zero_of_finite, mt index_eq_one.mp hH⟩
@@ -914,12 +626,6 @@ instance [FiniteIndex H] [FiniteIndex K] : FiniteIndex (H ⊓ K) :=
 
 variable {H K}
 
-/- warning: subgroup.finite_index_of_le -> Subgroup.finiteIndex_of_le is a dubious translation:
-lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1} [_inst_2 : Subgroup.FiniteIndex.{u1} G _inst_1 H], (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toHasLe.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (SetLike.partialOrder.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)))) H K) -> (Subgroup.FiniteIndex.{u1} G _inst_1 K)
-but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1} [_inst_2 : Subgroup.FiniteIndex.{u1} G _inst_1 H], (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toLE.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (CompleteSemilatticeInf.toPartialOrder.{u1} (Subgroup.{u1} G _inst_1) (CompleteLattice.toCompleteSemilatticeInf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instCompleteLatticeSubgroup.{u1} G _inst_1))))) H K) -> (Subgroup.FiniteIndex.{u1} G _inst_1 K)
-Case conversion may be inaccurate. Consider using '#align subgroup.finite_index_of_le Subgroup.finiteIndex_of_leₓ'. -/
 @[to_additive]
 theorem finiteIndex_of_le [FiniteIndex H] (h : H ≤ K) : FiniteIndex K :=
   ⟨ne_zero_of_dvd_ne_zero FiniteIndex.finiteIndex (index_dvd_of_le h)⟩
@@ -928,12 +634,6 @@ theorem finiteIndex_of_le [FiniteIndex H] (h : H ≤ K) : FiniteIndex K :=
 
 variable (H K)
 
-/- warning: subgroup.finite_index_ker -> Subgroup.finiteIndex_ker is a dubious translation:
-lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {G' : Type.{u2}} [_inst_2 : Group.{u2} G'] (f : MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) [_inst_3 : Finite.{succ u2} (coeSort.{succ u2, succ (succ u2)} (Subgroup.{u2} G' _inst_2) Type.{u2} (SetLike.hasCoeToSort.{u2, u2} (Subgroup.{u2} G' _inst_2) G' (Subgroup.setLike.{u2} G' _inst_2)) (MonoidHom.range.{u1, u2} G _inst_1 G' _inst_2 f))], Subgroup.FiniteIndex.{u1} G _inst_1 (MonoidHom.ker.{u1, u2} G _inst_1 G' (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) f)
-but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {G' : Type.{u2}} [_inst_2 : Group.{u2} G'] (f : MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) [_inst_3 : Finite.{succ u2} (Subtype.{succ u2} G' (fun (x : G') => Membership.mem.{u2, u2} G' (Subgroup.{u2} G' _inst_2) (SetLike.instMembership.{u2, u2} (Subgroup.{u2} G' _inst_2) G' (Subgroup.instSetLikeSubgroup.{u2} G' _inst_2)) x (MonoidHom.range.{u1, u2} G _inst_1 G' _inst_2 f)))], Subgroup.FiniteIndex.{u1} G _inst_1 (MonoidHom.ker.{u1, u2} G _inst_1 G' (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) f)
-Case conversion may be inaccurate. Consider using '#align subgroup.finite_index_ker Subgroup.finiteIndex_kerₓ'. -/
 @[to_additive]
 instance finiteIndex_ker {G' : Type _} [Group G'] (f : G →* G') [Finite f.range] :
     f.ker.FiniteIndex :=

mathlib commit https://github.com/leanprover-community/mathlib/commit/917c3c072e487b3cccdbfeff17e75b40e45f66cb

@@ -284,8 +284,7 @@ theorem index_eq_two_iff : H.index = 2 ↔ ∃ a, ∀ b, Xor' (b * a ∈ H) (b 
     exists_congr fun a => ⟨fun ha b => ⟨fun hba hb => _, fun hb => _⟩, fun ha => ⟨_, fun b hb => _⟩⟩
   · exact ha.1 ((mul_mem_cancel_left hb).1 hba)
   · exact inv_inv b ▸ ha.2 _ (mt inv_mem_iff.1 hb)
-  · rw [← inv_mem_iff, ← ha, inv_mul_self]
-    exact one_mem _
+  · rw [← inv_mem_iff, ← ha, inv_mul_self]; exact one_mem _
   · rwa [ha, inv_mem_iff]
 #align subgroup.index_eq_two_iff Subgroup.index_eq_two_iff
 #align add_subgroup.index_eq_two_iff AddSubgroup.index_eq_two_iff
@@ -443,10 +442,8 @@ but is expected to have type
   forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Type.{u2}} [_inst_2 : Group.{u2} H] (f : MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))), Eq.{1} Nat (Subgroup.index.{u1} G _inst_1 (MonoidHom.ker.{u1, u2} G _inst_1 H (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2))) f)) (Nat.card.{u2} (Set.Elem.{u2} H (Set.range.{u2, succ u1} H G (FunLike.coe.{max (succ u1) (succ u2), succ u1, succ u2} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) G (fun (_x : G) => (fun (x._@.Mathlib.Algebra.Hom.Group._hyg.2397 : G) => H) _x) (MulHomClass.toFunLike.{max u1 u2, u1, u2} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) G H (MulOneClass.toMul.{u1} G (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) (MulOneClass.toMul.{u2} H (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) (MonoidHomClass.toMulHomClass.{max u1 u2, u1, u2} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2))) (MonoidHom.monoidHomClass.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))))) f))))
 Case conversion may be inaccurate. Consider using '#align subgroup.index_ker Subgroup.index_kerₓ'. -/
 @[to_additive]
-theorem index_ker {H} [Group H] (f : G →* H) : f.ker.index = Nat.card (Set.range f) :=
-  by
-  rw [← MonoidHom.comap_bot, index_comap, relindex_bot_left]
-  rfl
+theorem index_ker {H} [Group H] (f : G →* H) : f.ker.index = Nat.card (Set.range f) := by
+  rw [← MonoidHom.comap_bot, index_comap, relindex_bot_left]; rfl
 #align subgroup.index_ker Subgroup.index_ker
 #align add_subgroup.index_ker AddSubgroup.index_ker
 
@@ -458,10 +455,8 @@ but is expected to have type
 Case conversion may be inaccurate. Consider using '#align subgroup.relindex_ker Subgroup.relindex_kerₓ'. -/
 @[to_additive]
 theorem relindex_ker {H} [Group H] (f : G →* H) (K : Subgroup G) :
-    f.ker.relindex K = Nat.card (f '' K) :=
-  by
-  rw [← MonoidHom.comap_bot, relindex_comap, relindex_bot_left]
-  rfl
+    f.ker.relindex K = Nat.card (f '' K) := by
+  rw [← MonoidHom.comap_bot, relindex_comap, relindex_bot_left]; rfl
 #align subgroup.relindex_ker Subgroup.relindex_ker
 #align add_subgroup.relindex_ker AddSubgroup.relindex_ker
 
@@ -472,10 +467,8 @@ but is expected to have type
   forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1), Eq.{1} Nat (HMul.hMul.{0, 0, 0} Nat Nat Nat (instHMul.{0} Nat instMulNat) (Nat.card.{u1} (Subtype.{succ u1} G (fun (x : G) => Membership.mem.{u1, u1} G (Subgroup.{u1} G _inst_1) (SetLike.instMembership.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.instSetLikeSubgroup.{u1} G _inst_1)) x H))) (Subgroup.index.{u1} G _inst_1 H)) (Nat.card.{u1} G)
 Case conversion may be inaccurate. Consider using '#align subgroup.card_mul_index Subgroup.card_mul_indexₓ'. -/
 @[simp, to_additive card_mul_index]
-theorem card_mul_index : Nat.card H * H.index = Nat.card G :=
-  by
-  rw [← relindex_bot_left, ← index_bot]
-  exact relindex_mul_index bot_le
+theorem card_mul_index : Nat.card H * H.index = Nat.card G := by
+  rw [← relindex_bot_left, ← index_bot]; exact relindex_mul_index bot_le
 #align subgroup.card_mul_index Subgroup.card_mul_index
 #align add_subgroup.card_mul_index AddSubgroup.card_mul_index
 
@@ -833,11 +826,8 @@ theorem card_eq_one : Nat.card H = 1 ↔ H = ⊥ :=
 
 #print Subgroup.index_ne_zero_of_finite /-
 @[to_additive]
-theorem index_ne_zero_of_finite [hH : Finite (G ⧸ H)] : H.index ≠ 0 :=
-  by
-  cases nonempty_fintype (G ⧸ H)
-  rw [index_eq_card]
-  exact Fintype.card_ne_zero
+theorem index_ne_zero_of_finite [hH : Finite (G ⧸ H)] : H.index ≠ 0 := by
+  cases nonempty_fintype (G ⧸ H); rw [index_eq_card]; exact Fintype.card_ne_zero
 #align subgroup.index_ne_zero_of_finite Subgroup.index_ne_zero_of_finite
 #align add_subgroup.index_ne_zero_of_finite AddSubgroup.index_ne_zero_of_finite
 -/

mathlib commit https://github.com/leanprover-community/mathlib/commit/95a87616d63b3cb49d3fe678d416fbe9c4217bf4

@@ -71,7 +71,7 @@ noncomputable def relindex : ℕ :=
 lean 3 declaration is
   forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) {G' : Type.{u2}} [_inst_2 : Group.{u2} G'] {f : MonoidHom.{u2, u1} G' G (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))}, (Function.Surjective.{succ u2, succ u1} G' G (coeFn.{max (succ u1) (succ u2), max (succ u2) (succ u1)} (MonoidHom.{u2, u1} G' G (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) (fun (_x : MonoidHom.{u2, u1} G' G (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) => G' -> G) (MonoidHom.hasCoeToFun.{u2, u1} G' G (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) f)) -> (Eq.{1} Nat (Subgroup.index.{u2} G' _inst_2 (Subgroup.comap.{u2, u1} G' _inst_2 G _inst_1 f H)) (Subgroup.index.{u1} G _inst_1 H))
 but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) {G' : Type.{u2}} [_inst_2 : Group.{u2} G'] {f : MonoidHom.{u2, u1} G' G (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))}, (Function.Surjective.{succ u2, succ u1} G' G (FunLike.coe.{max (succ u1) (succ u2), succ u2, succ u1} (MonoidHom.{u2, u1} G' G (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) G' (fun (_x : G') => (fun (x._@.Mathlib.Algebra.Hom.Group._hyg.2391 : G') => G) _x) (MulHomClass.toFunLike.{max u1 u2, u2, u1} (MonoidHom.{u2, u1} G' G (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) G' G (MulOneClass.toMul.{u2} G' (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) (MulOneClass.toMul.{u1} G (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) (MonoidHomClass.toMulHomClass.{max u1 u2, u2, u1} (MonoidHom.{u2, u1} G' G (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) G' G (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (MonoidHom.monoidHomClass.{u2, u1} G' G (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))))) f)) -> (Eq.{1} Nat (Subgroup.index.{u2} G' _inst_2 (Subgroup.comap.{u2, u1} G' _inst_2 G _inst_1 f H)) (Subgroup.index.{u1} G _inst_1 H))
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) {G' : Type.{u2}} [_inst_2 : Group.{u2} G'] {f : MonoidHom.{u2, u1} G' G (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))}, (Function.Surjective.{succ u2, succ u1} G' G (FunLike.coe.{max (succ u1) (succ u2), succ u2, succ u1} (MonoidHom.{u2, u1} G' G (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) G' (fun (_x : G') => (fun (x._@.Mathlib.Algebra.Hom.Group._hyg.2397 : G') => G) _x) (MulHomClass.toFunLike.{max u1 u2, u2, u1} (MonoidHom.{u2, u1} G' G (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) G' G (MulOneClass.toMul.{u2} G' (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) (MulOneClass.toMul.{u1} G (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) (MonoidHomClass.toMulHomClass.{max u1 u2, u2, u1} (MonoidHom.{u2, u1} G' G (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) G' G (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (MonoidHom.monoidHomClass.{u2, u1} G' G (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))))) f)) -> (Eq.{1} Nat (Subgroup.index.{u2} G' _inst_2 (Subgroup.comap.{u2, u1} G' _inst_2 G _inst_1 f H)) (Subgroup.index.{u1} G _inst_1 H))
 Case conversion may be inaccurate. Consider using '#align subgroup.index_comap_of_surjective Subgroup.index_comap_of_surjectiveₓ'. -/
 @[to_additive]
 theorem index_comap_of_surjective {G' : Type _} [Group G'] {f : G' →* G}
@@ -440,7 +440,7 @@ theorem relindex_self : H.relindex H = 1 := by rw [relindex, subgroup_of_self, i
 lean 3 declaration is
   forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Type.{u2}} [_inst_2 : Group.{u2} H] (f : MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))), Eq.{1} Nat (Subgroup.index.{u1} G _inst_1 (MonoidHom.ker.{u1, u2} G _inst_1 H (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2))) f)) (Nat.card.{u2} (coeSort.{succ u2, succ (succ u2)} (Set.{u2} H) Type.{u2} (Set.hasCoeToSort.{u2} H) (Set.range.{u2, succ u1} H G (coeFn.{max (succ u2) (succ u1), max (succ u1) (succ u2)} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) (fun (_x : MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) => G -> H) (MonoidHom.hasCoeToFun.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) f))))
 but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Type.{u2}} [_inst_2 : Group.{u2} H] (f : MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))), Eq.{1} Nat (Subgroup.index.{u1} G _inst_1 (MonoidHom.ker.{u1, u2} G _inst_1 H (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2))) f)) (Nat.card.{u2} (Set.Elem.{u2} H (Set.range.{u2, succ u1} H G (FunLike.coe.{max (succ u1) (succ u2), succ u1, succ u2} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) G (fun (_x : G) => (fun (x._@.Mathlib.Algebra.Hom.Group._hyg.2391 : G) => H) _x) (MulHomClass.toFunLike.{max u1 u2, u1, u2} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) G H (MulOneClass.toMul.{u1} G (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) (MulOneClass.toMul.{u2} H (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) (MonoidHomClass.toMulHomClass.{max u1 u2, u1, u2} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2))) (MonoidHom.monoidHomClass.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))))) f))))
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Type.{u2}} [_inst_2 : Group.{u2} H] (f : MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))), Eq.{1} Nat (Subgroup.index.{u1} G _inst_1 (MonoidHom.ker.{u1, u2} G _inst_1 H (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2))) f)) (Nat.card.{u2} (Set.Elem.{u2} H (Set.range.{u2, succ u1} H G (FunLike.coe.{max (succ u1) (succ u2), succ u1, succ u2} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) G (fun (_x : G) => (fun (x._@.Mathlib.Algebra.Hom.Group._hyg.2397 : G) => H) _x) (MulHomClass.toFunLike.{max u1 u2, u1, u2} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) G H (MulOneClass.toMul.{u1} G (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) (MulOneClass.toMul.{u2} H (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) (MonoidHomClass.toMulHomClass.{max u1 u2, u1, u2} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2))) (MonoidHom.monoidHomClass.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))))) f))))
 Case conversion may be inaccurate. Consider using '#align subgroup.index_ker Subgroup.index_kerₓ'. -/
 @[to_additive]
 theorem index_ker {H} [Group H] (f : G →* H) : f.ker.index = Nat.card (Set.range f) :=
@@ -454,7 +454,7 @@ theorem index_ker {H} [Group H] (f : G →* H) : f.ker.index = Nat.card (Set.ran
 lean 3 declaration is
   forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Type.{u2}} [_inst_2 : Group.{u2} H] (f : MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) (K : Subgroup.{u1} G _inst_1), Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 (MonoidHom.ker.{u1, u2} G _inst_1 H (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2))) f) K) (Nat.card.{u2} (coeSort.{succ u2, succ (succ u2)} (Set.{u2} H) Type.{u2} (Set.hasCoeToSort.{u2} H) (Set.image.{u1, u2} G H (coeFn.{max (succ u2) (succ u1), max (succ u1) (succ u2)} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) (fun (_x : MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) => G -> H) (MonoidHom.hasCoeToFun.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) f) ((fun (a : Type.{u1}) (b : Type.{u1}) [self : HasLiftT.{succ u1, succ u1} a b] => self.0) (Subgroup.{u1} G _inst_1) (Set.{u1} G) (HasLiftT.mk.{succ u1, succ u1} (Subgroup.{u1} G _inst_1) (Set.{u1} G) (CoeTCₓ.coe.{succ u1, succ u1} (Subgroup.{u1} G _inst_1) (Set.{u1} G) (SetLike.Set.hasCoeT.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)))) K))))
 but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Type.{u2}} [_inst_2 : Group.{u2} H] (f : MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) (K : Subgroup.{u1} G _inst_1), Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 (MonoidHom.ker.{u1, u2} G _inst_1 H (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2))) f) K) (Nat.card.{u2} (Set.Elem.{u2} H (Set.image.{u1, u2} G H (FunLike.coe.{max (succ u1) (succ u2), succ u1, succ u2} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) G (fun (_x : G) => (fun (x._@.Mathlib.Algebra.Hom.Group._hyg.2391 : G) => H) _x) (MulHomClass.toFunLike.{max u1 u2, u1, u2} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) G H (MulOneClass.toMul.{u1} G (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) (MulOneClass.toMul.{u2} H (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) (MonoidHomClass.toMulHomClass.{max u1 u2, u1, u2} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2))) (MonoidHom.monoidHomClass.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))))) f) (SetLike.coe.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.instSetLikeSubgroup.{u1} G _inst_1) K))))
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Type.{u2}} [_inst_2 : Group.{u2} H] (f : MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) (K : Subgroup.{u1} G _inst_1), Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 (MonoidHom.ker.{u1, u2} G _inst_1 H (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2))) f) K) (Nat.card.{u2} (Set.Elem.{u2} H (Set.image.{u1, u2} G H (FunLike.coe.{max (succ u1) (succ u2), succ u1, succ u2} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) G (fun (_x : G) => (fun (x._@.Mathlib.Algebra.Hom.Group._hyg.2397 : G) => H) _x) (MulHomClass.toFunLike.{max u1 u2, u1, u2} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) G H (MulOneClass.toMul.{u1} G (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) (MulOneClass.toMul.{u2} H (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) (MonoidHomClass.toMulHomClass.{max u1 u2, u1, u2} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2))) (MonoidHom.monoidHomClass.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))))) f) (SetLike.coe.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.instSetLikeSubgroup.{u1} G _inst_1) K))))
 Case conversion may be inaccurate. Consider using '#align subgroup.relindex_ker Subgroup.relindex_kerₓ'. -/
 @[to_additive]
 theorem relindex_ker {H} [Group H] (f : G →* H) (K : Subgroup G) :
@@ -483,7 +483,7 @@ theorem card_mul_index : Nat.card H * H.index = Nat.card G :=
 lean 3 declaration is
   forall {G : Type.{u1}} {H : Type.{u2}} [_inst_2 : Group.{u1} G] [_inst_3 : Group.{u2} H] (f : MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_2))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_3)))), (Function.Injective.{succ u1, succ u2} G H (coeFn.{max (succ u2) (succ u1), max (succ u1) (succ u2)} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_2))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_3)))) (fun (_x : MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_2))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_3)))) => G -> H) (MonoidHom.hasCoeToFun.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_2))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_3)))) f)) -> (Dvd.Dvd.{0} Nat Nat.hasDvd (Nat.card.{u1} G) (Nat.card.{u2} H))
 but is expected to have type
-  forall {G : Type.{u2}} {H : Type.{u1}} [_inst_2 : Group.{u2} G] [_inst_3 : Group.{u1} H] (f : MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))), (Function.Injective.{succ u2, succ u1} G H (FunLike.coe.{max (succ u2) (succ u1), succ u2, succ u1} (MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) G (fun (_x : G) => (fun (x._@.Mathlib.Algebra.Hom.Group._hyg.2391 : G) => H) _x) (MulHomClass.toFunLike.{max u2 u1, u2, u1} (MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) G H (MulOneClass.toMul.{u2} G (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2)))) (MulOneClass.toMul.{u1} H (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) (MonoidHomClass.toMulHomClass.{max u2 u1, u2, u1} (MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3))) (MonoidHom.monoidHomClass.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))))) f)) -> (Dvd.dvd.{0} Nat Nat.instDvdNat (Nat.card.{u2} G) (Nat.card.{u1} H))
+  forall {G : Type.{u2}} {H : Type.{u1}} [_inst_2 : Group.{u2} G] [_inst_3 : Group.{u1} H] (f : MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))), (Function.Injective.{succ u2, succ u1} G H (FunLike.coe.{max (succ u2) (succ u1), succ u2, succ u1} (MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) G (fun (_x : G) => (fun (x._@.Mathlib.Algebra.Hom.Group._hyg.2397 : G) => H) _x) (MulHomClass.toFunLike.{max u2 u1, u2, u1} (MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) G H (MulOneClass.toMul.{u2} G (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2)))) (MulOneClass.toMul.{u1} H (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) (MonoidHomClass.toMulHomClass.{max u2 u1, u2, u1} (MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3))) (MonoidHom.monoidHomClass.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))))) f)) -> (Dvd.dvd.{0} Nat Nat.instDvdNat (Nat.card.{u2} G) (Nat.card.{u1} H))
 Case conversion may be inaccurate. Consider using '#align subgroup.nat_card_dvd_of_injective Subgroup.nat_card_dvd_of_injectiveₓ'. -/
 @[to_additive]
 theorem nat_card_dvd_of_injective {G H : Type _} [Group G] [Group H] (f : G →* H)
@@ -510,7 +510,7 @@ theorem nat_card_dvd_of_le (hHK : H ≤ K) : Nat.card H ∣ Nat.card K :=
 lean 3 declaration is
   forall {G : Type.{u1}} {H : Type.{u2}} [_inst_2 : Group.{u1} G] [_inst_3 : Group.{u2} H] (f : MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_2))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_3)))), (Function.Surjective.{succ u1, succ u2} G H (coeFn.{max (succ u2) (succ u1), max (succ u1) (succ u2)} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_2))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_3)))) (fun (_x : MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_2))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_3)))) => G -> H) (MonoidHom.hasCoeToFun.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_2))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_3)))) f)) -> (Dvd.Dvd.{0} Nat Nat.hasDvd (Nat.card.{u2} H) (Nat.card.{u1} G))
 but is expected to have type
-  forall {G : Type.{u2}} {H : Type.{u1}} [_inst_2 : Group.{u2} G] [_inst_3 : Group.{u1} H] (f : MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))), (Function.Surjective.{succ u2, succ u1} G H (FunLike.coe.{max (succ u2) (succ u1), succ u2, succ u1} (MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) G (fun (_x : G) => (fun (x._@.Mathlib.Algebra.Hom.Group._hyg.2391 : G) => H) _x) (MulHomClass.toFunLike.{max u2 u1, u2, u1} (MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) G H (MulOneClass.toMul.{u2} G (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2)))) (MulOneClass.toMul.{u1} H (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) (MonoidHomClass.toMulHomClass.{max u2 u1, u2, u1} (MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3))) (MonoidHom.monoidHomClass.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))))) f)) -> (Dvd.dvd.{0} Nat Nat.instDvdNat (Nat.card.{u1} H) (Nat.card.{u2} G))
+  forall {G : Type.{u2}} {H : Type.{u1}} [_inst_2 : Group.{u2} G] [_inst_3 : Group.{u1} H] (f : MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))), (Function.Surjective.{succ u2, succ u1} G H (FunLike.coe.{max (succ u2) (succ u1), succ u2, succ u1} (MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) G (fun (_x : G) => (fun (x._@.Mathlib.Algebra.Hom.Group._hyg.2397 : G) => H) _x) (MulHomClass.toFunLike.{max u2 u1, u2, u1} (MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) G H (MulOneClass.toMul.{u2} G (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2)))) (MulOneClass.toMul.{u1} H (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) (MonoidHomClass.toMulHomClass.{max u2 u1, u2, u1} (MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3))) (MonoidHom.monoidHomClass.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))))) f)) -> (Dvd.dvd.{0} Nat Nat.instDvdNat (Nat.card.{u1} H) (Nat.card.{u2} G))
 Case conversion may be inaccurate. Consider using '#align subgroup.nat_card_dvd_of_surjective Subgroup.nat_card_dvd_of_surjectiveₓ'. -/
 @[to_additive]
 theorem nat_card_dvd_of_surjective {G H : Type _} [Group G] [Group H] (f : G →* H)
@@ -525,7 +525,7 @@ theorem nat_card_dvd_of_surjective {G H : Type _} [Group G] [Group H] (f : G →
 lean 3 declaration is
   forall {G : Type.{u1}} {H : Type.{u2}} [_inst_2 : Group.{u1} G] [_inst_3 : Group.{u2} H] [_inst_4 : Fintype.{u1} G] [_inst_5 : Fintype.{u2} H] (f : MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_2))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_3)))), (Function.Surjective.{succ u1, succ u2} G H (coeFn.{max (succ u2) (succ u1), max (succ u1) (succ u2)} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_2))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_3)))) (fun (_x : MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_2))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_3)))) => G -> H) (MonoidHom.hasCoeToFun.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_2))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_3)))) f)) -> (Dvd.Dvd.{0} Nat Nat.hasDvd (Fintype.card.{u2} H _inst_5) (Fintype.card.{u1} G _inst_4))
 but is expected to have type
-  forall {G : Type.{u2}} {H : Type.{u1}} [_inst_2 : Group.{u2} G] [_inst_3 : Group.{u1} H] [_inst_4 : Fintype.{u2} G] [_inst_5 : Fintype.{u1} H] (f : MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))), (Function.Surjective.{succ u2, succ u1} G H (FunLike.coe.{max (succ u2) (succ u1), succ u2, succ u1} (MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) G (fun (_x : G) => (fun (x._@.Mathlib.Algebra.Hom.Group._hyg.2391 : G) => H) _x) (MulHomClass.toFunLike.{max u2 u1, u2, u1} (MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) G H (MulOneClass.toMul.{u2} G (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2)))) (MulOneClass.toMul.{u1} H (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) (MonoidHomClass.toMulHomClass.{max u2 u1, u2, u1} (MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3))) (MonoidHom.monoidHomClass.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))))) f)) -> (Dvd.dvd.{0} Nat Nat.instDvdNat (Fintype.card.{u1} H _inst_5) (Fintype.card.{u2} G _inst_4))
+  forall {G : Type.{u2}} {H : Type.{u1}} [_inst_2 : Group.{u2} G] [_inst_3 : Group.{u1} H] [_inst_4 : Fintype.{u2} G] [_inst_5 : Fintype.{u1} H] (f : MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))), (Function.Surjective.{succ u2, succ u1} G H (FunLike.coe.{max (succ u2) (succ u1), succ u2, succ u1} (MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) G (fun (_x : G) => (fun (x._@.Mathlib.Algebra.Hom.Group._hyg.2397 : G) => H) _x) (MulHomClass.toFunLike.{max u2 u1, u2, u1} (MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) G H (MulOneClass.toMul.{u2} G (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2)))) (MulOneClass.toMul.{u1} H (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) (MonoidHomClass.toMulHomClass.{max u2 u1, u2, u1} (MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3))) (MonoidHom.monoidHomClass.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))))) f)) -> (Dvd.dvd.{0} Nat Nat.instDvdNat (Fintype.card.{u1} H _inst_5) (Fintype.card.{u2} G _inst_4))
 Case conversion may be inaccurate. Consider using '#align subgroup.card_dvd_of_surjective Subgroup.card_dvd_of_surjectiveₓ'. -/
 @[to_additive]
 theorem card_dvd_of_surjective {G H : Type _} [Group G] [Group H] [Fintype G] [Fintype H]
@@ -551,7 +551,7 @@ theorem index_map {G' : Type _} [Group G'] (f : G →* G') :
 lean 3 declaration is
   forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) {G' : Type.{u2}} [_inst_2 : Group.{u2} G'] {f : MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))}, (Function.Surjective.{succ u1, succ u2} G G' (coeFn.{max (succ u2) (succ u1), max (succ u1) (succ u2)} (MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) (fun (_x : MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) => G -> G') (MonoidHom.hasCoeToFun.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) f)) -> (Dvd.Dvd.{0} Nat Nat.hasDvd (Subgroup.index.{u2} G' _inst_2 (Subgroup.map.{u1, u2} G _inst_1 G' _inst_2 f H)) (Subgroup.index.{u1} G _inst_1 H))
 but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) {G' : Type.{u2}} [_inst_2 : Group.{u2} G'] {f : MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))}, (Function.Surjective.{succ u1, succ u2} G G' (FunLike.coe.{max (succ u1) (succ u2), succ u1, succ u2} (MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) G (fun (_x : G) => (fun (x._@.Mathlib.Algebra.Hom.Group._hyg.2391 : G) => G') _x) (MulHomClass.toFunLike.{max u1 u2, u1, u2} (MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) G G' (MulOneClass.toMul.{u1} G (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) (MulOneClass.toMul.{u2} G' (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) (MonoidHomClass.toMulHomClass.{max u1 u2, u1, u2} (MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (MonoidHom.monoidHomClass.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))))) f)) -> (Dvd.dvd.{0} Nat Nat.instDvdNat (Subgroup.index.{u2} G' _inst_2 (Subgroup.map.{u1, u2} G _inst_1 G' _inst_2 f H)) (Subgroup.index.{u1} G _inst_1 H))
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) {G' : Type.{u2}} [_inst_2 : Group.{u2} G'] {f : MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))}, (Function.Surjective.{succ u1, succ u2} G G' (FunLike.coe.{max (succ u1) (succ u2), succ u1, succ u2} (MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) G (fun (_x : G) => (fun (x._@.Mathlib.Algebra.Hom.Group._hyg.2397 : G) => G') _x) (MulHomClass.toFunLike.{max u1 u2, u1, u2} (MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) G G' (MulOneClass.toMul.{u1} G (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) (MulOneClass.toMul.{u2} G' (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) (MonoidHomClass.toMulHomClass.{max u1 u2, u1, u2} (MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (MonoidHom.monoidHomClass.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))))) f)) -> (Dvd.dvd.{0} Nat Nat.instDvdNat (Subgroup.index.{u2} G' _inst_2 (Subgroup.map.{u1, u2} G _inst_1 G' _inst_2 f H)) (Subgroup.index.{u1} G _inst_1 H))
 Case conversion may be inaccurate. Consider using '#align subgroup.index_map_dvd Subgroup.index_map_dvdₓ'. -/
 @[to_additive]
 theorem index_map_dvd {G' : Type _} [Group G'] {f : G →* G'} (hf : Function.Surjective f) :
@@ -580,7 +580,7 @@ theorem dvd_index_map {G' : Type _} [Group G'] {f : G →* G'} (hf : f.ker ≤ H
 lean 3 declaration is
   forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) {G' : Type.{u2}} [_inst_2 : Group.{u2} G'] {f : MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))}, (Function.Surjective.{succ u1, succ u2} G G' (coeFn.{max (succ u2) (succ u1), max (succ u1) (succ u2)} (MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) (fun (_x : MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) => G -> G') (MonoidHom.hasCoeToFun.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) f)) -> (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toHasLe.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (SetLike.partialOrder.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)))) (MonoidHom.ker.{u1, u2} G _inst_1 G' (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) f) H) -> (Eq.{1} Nat (Subgroup.index.{u2} G' _inst_2 (Subgroup.map.{u1, u2} G _inst_1 G' _inst_2 f H)) (Subgroup.index.{u1} G _inst_1 H))
 but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) {G' : Type.{u2}} [_inst_2 : Group.{u2} G'] {f : MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))}, (Function.Surjective.{succ u1, succ u2} G G' (FunLike.coe.{max (succ u1) (succ u2), succ u1, succ u2} (MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) G (fun (_x : G) => (fun (x._@.Mathlib.Algebra.Hom.Group._hyg.2391 : G) => G') _x) (MulHomClass.toFunLike.{max u1 u2, u1, u2} (MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) G G' (MulOneClass.toMul.{u1} G (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) (MulOneClass.toMul.{u2} G' (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) (MonoidHomClass.toMulHomClass.{max u1 u2, u1, u2} (MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (MonoidHom.monoidHomClass.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))))) f)) -> (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toLE.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (CompleteSemilatticeInf.toPartialOrder.{u1} (Subgroup.{u1} G _inst_1) (CompleteLattice.toCompleteSemilatticeInf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instCompleteLatticeSubgroup.{u1} G _inst_1))))) (MonoidHom.ker.{u1, u2} G _inst_1 G' (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) f) H) -> (Eq.{1} Nat (Subgroup.index.{u2} G' _inst_2 (Subgroup.map.{u1, u2} G _inst_1 G' _inst_2 f H)) (Subgroup.index.{u1} G _inst_1 H))
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) {G' : Type.{u2}} [_inst_2 : Group.{u2} G'] {f : MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))}, (Function.Surjective.{succ u1, succ u2} G G' (FunLike.coe.{max (succ u1) (succ u2), succ u1, succ u2} (MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) G (fun (_x : G) => (fun (x._@.Mathlib.Algebra.Hom.Group._hyg.2397 : G) => G') _x) (MulHomClass.toFunLike.{max u1 u2, u1, u2} (MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) G G' (MulOneClass.toMul.{u1} G (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) (MulOneClass.toMul.{u2} G' (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) (MonoidHomClass.toMulHomClass.{max u1 u2, u1, u2} (MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (MonoidHom.monoidHomClass.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))))) f)) -> (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toLE.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (CompleteSemilatticeInf.toPartialOrder.{u1} (Subgroup.{u1} G _inst_1) (CompleteLattice.toCompleteSemilatticeInf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instCompleteLatticeSubgroup.{u1} G _inst_1))))) (MonoidHom.ker.{u1, u2} G _inst_1 G' (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) f) H) -> (Eq.{1} Nat (Subgroup.index.{u2} G' _inst_2 (Subgroup.map.{u1, u2} G _inst_1 G' _inst_2 f H)) (Subgroup.index.{u1} G _inst_1 H))
 Case conversion may be inaccurate. Consider using '#align subgroup.index_map_eq Subgroup.index_map_eqₓ'. -/
 @[to_additive]
 theorem index_map_eq {G' : Type _} [Group G'] {f : G →* G'} (hf1 : Function.Surjective f)

mathlib commit https://github.com/leanprover-community/mathlib/commit/0b9eaaa7686280fad8cce467f5c3c57ee6ce77f8

@@ -117,7 +117,7 @@ variable {H K L}
 
 /- warning: subgroup.relindex_mul_index -> Subgroup.relindex_mul_index is a dubious translation:
 lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1}, (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toLE.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (SetLike.partialOrder.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)))) H K) -> (Eq.{1} Nat (HMul.hMul.{0, 0, 0} Nat Nat Nat (instHMul.{0} Nat Nat.hasMul) (Subgroup.relindex.{u1} G _inst_1 H K) (Subgroup.index.{u1} G _inst_1 K)) (Subgroup.index.{u1} G _inst_1 H))
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1}, (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toHasLe.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (SetLike.partialOrder.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)))) H K) -> (Eq.{1} Nat (HMul.hMul.{0, 0, 0} Nat Nat Nat (instHMul.{0} Nat Nat.hasMul) (Subgroup.relindex.{u1} G _inst_1 H K) (Subgroup.index.{u1} G _inst_1 K)) (Subgroup.index.{u1} G _inst_1 H))
 but is expected to have type
   forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1}, (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toLE.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (CompleteSemilatticeInf.toPartialOrder.{u1} (Subgroup.{u1} G _inst_1) (CompleteLattice.toCompleteSemilatticeInf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instCompleteLatticeSubgroup.{u1} G _inst_1))))) H K) -> (Eq.{1} Nat (HMul.hMul.{0, 0, 0} Nat Nat Nat (instHMul.{0} Nat instMulNat) (Subgroup.relindex.{u1} G _inst_1 H K) (Subgroup.index.{u1} G _inst_1 K)) (Subgroup.index.{u1} G _inst_1 H))
 Case conversion may be inaccurate. Consider using '#align subgroup.relindex_mul_index Subgroup.relindex_mul_indexₓ'. -/
@@ -130,7 +130,7 @@ theorem relindex_mul_index (h : H ≤ K) : H.relindex K * K.index = H.index :=
 
 /- warning: subgroup.index_dvd_of_le -> Subgroup.index_dvd_of_le is a dubious translation:
 lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1}, (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toLE.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (SetLike.partialOrder.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)))) H K) -> (Dvd.Dvd.{0} Nat Nat.hasDvd (Subgroup.index.{u1} G _inst_1 K) (Subgroup.index.{u1} G _inst_1 H))
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1}, (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toHasLe.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (SetLike.partialOrder.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)))) H K) -> (Dvd.Dvd.{0} Nat Nat.hasDvd (Subgroup.index.{u1} G _inst_1 K) (Subgroup.index.{u1} G _inst_1 H))
 but is expected to have type
   forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1}, (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toLE.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (CompleteSemilatticeInf.toPartialOrder.{u1} (Subgroup.{u1} G _inst_1) (CompleteLattice.toCompleteSemilatticeInf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instCompleteLatticeSubgroup.{u1} G _inst_1))))) H K) -> (Dvd.dvd.{0} Nat Nat.instDvdNat (Subgroup.index.{u1} G _inst_1 K) (Subgroup.index.{u1} G _inst_1 H))
 Case conversion may be inaccurate. Consider using '#align subgroup.index_dvd_of_le Subgroup.index_dvd_of_leₓ'. -/
@@ -142,7 +142,7 @@ theorem index_dvd_of_le (h : H ≤ K) : K.index ∣ H.index :=
 
 /- warning: subgroup.relindex_dvd_index_of_le -> Subgroup.relindex_dvd_index_of_le is a dubious translation:
 lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1}, (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toLE.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (SetLike.partialOrder.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)))) H K) -> (Dvd.Dvd.{0} Nat Nat.hasDvd (Subgroup.relindex.{u1} G _inst_1 H K) (Subgroup.index.{u1} G _inst_1 H))
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1}, (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toHasLe.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (SetLike.partialOrder.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)))) H K) -> (Dvd.Dvd.{0} Nat Nat.hasDvd (Subgroup.relindex.{u1} G _inst_1 H K) (Subgroup.index.{u1} G _inst_1 H))
 but is expected to have type
   forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1}, (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toLE.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (CompleteSemilatticeInf.toPartialOrder.{u1} (Subgroup.{u1} G _inst_1) (CompleteLattice.toCompleteSemilatticeInf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instCompleteLatticeSubgroup.{u1} G _inst_1))))) H K) -> (Dvd.dvd.{0} Nat Nat.instDvdNat (Subgroup.relindex.{u1} G _inst_1 H K) (Subgroup.index.{u1} G _inst_1 H))
 Case conversion may be inaccurate. Consider using '#align subgroup.relindex_dvd_index_of_le Subgroup.relindex_dvd_index_of_leₓ'. -/
@@ -154,7 +154,7 @@ theorem relindex_dvd_index_of_le (h : H ≤ K) : H.relindex K ∣ H.index :=
 
 /- warning: subgroup.relindex_subgroup_of -> Subgroup.relindex_subgroupOf is a dubious translation:
 lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1} {L : Subgroup.{u1} G _inst_1}, (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toLE.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (SetLike.partialOrder.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)))) K L) -> (Eq.{1} Nat (Subgroup.relindex.{u1} (coeSort.{succ u1, succ (succ u1)} (Subgroup.{u1} G _inst_1) Type.{u1} (SetLike.hasCoeToSort.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)) L) (Subgroup.toGroup.{u1} G _inst_1 L) (Subgroup.subgroupOf.{u1} G _inst_1 H L) (Subgroup.subgroupOf.{u1} G _inst_1 K L)) (Subgroup.relindex.{u1} G _inst_1 H K))
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1} {L : Subgroup.{u1} G _inst_1}, (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toHasLe.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (SetLike.partialOrder.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)))) K L) -> (Eq.{1} Nat (Subgroup.relindex.{u1} (coeSort.{succ u1, succ (succ u1)} (Subgroup.{u1} G _inst_1) Type.{u1} (SetLike.hasCoeToSort.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)) L) (Subgroup.toGroup.{u1} G _inst_1 L) (Subgroup.subgroupOf.{u1} G _inst_1 H L) (Subgroup.subgroupOf.{u1} G _inst_1 K L)) (Subgroup.relindex.{u1} G _inst_1 H K))
 but is expected to have type
   forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1} {L : Subgroup.{u1} G _inst_1}, (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toLE.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (CompleteSemilatticeInf.toPartialOrder.{u1} (Subgroup.{u1} G _inst_1) (CompleteLattice.toCompleteSemilatticeInf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instCompleteLatticeSubgroup.{u1} G _inst_1))))) K L) -> (Eq.{1} Nat (Subgroup.relindex.{u1} (Subtype.{succ u1} G (fun (x : G) => Membership.mem.{u1, u1} G (Subgroup.{u1} G _inst_1) (SetLike.instMembership.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.instSetLikeSubgroup.{u1} G _inst_1)) x L)) (Subgroup.toGroup.{u1} G _inst_1 L) (Subgroup.subgroupOf.{u1} G _inst_1 H L) (Subgroup.subgroupOf.{u1} G _inst_1 K L)) (Subgroup.relindex.{u1} G _inst_1 H K))
 Case conversion may be inaccurate. Consider using '#align subgroup.relindex_subgroup_of Subgroup.relindex_subgroupOfₓ'. -/
@@ -169,7 +169,7 @@ variable (H K L)
 
 /- warning: subgroup.relindex_mul_relindex -> Subgroup.relindex_mul_relindex is a dubious translation:
 lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) (K : Subgroup.{u1} G _inst_1) (L : Subgroup.{u1} G _inst_1), (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toLE.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (SetLike.partialOrder.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)))) H K) -> (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toLE.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (SetLike.partialOrder.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)))) K L) -> (Eq.{1} Nat (HMul.hMul.{0, 0, 0} Nat Nat Nat (instHMul.{0} Nat Nat.hasMul) (Subgroup.relindex.{u1} G _inst_1 H K) (Subgroup.relindex.{u1} G _inst_1 K L)) (Subgroup.relindex.{u1} G _inst_1 H L))
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) (K : Subgroup.{u1} G _inst_1) (L : Subgroup.{u1} G _inst_1), (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toHasLe.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (SetLike.partialOrder.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)))) H K) -> (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toHasLe.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (SetLike.partialOrder.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)))) K L) -> (Eq.{1} Nat (HMul.hMul.{0, 0, 0} Nat Nat Nat (instHMul.{0} Nat Nat.hasMul) (Subgroup.relindex.{u1} G _inst_1 H K) (Subgroup.relindex.{u1} G _inst_1 K L)) (Subgroup.relindex.{u1} G _inst_1 H L))
 but is expected to have type
   forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) (K : Subgroup.{u1} G _inst_1) (L : Subgroup.{u1} G _inst_1), (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toLE.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (CompleteSemilatticeInf.toPartialOrder.{u1} (Subgroup.{u1} G _inst_1) (CompleteLattice.toCompleteSemilatticeInf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instCompleteLatticeSubgroup.{u1} G _inst_1))))) H K) -> (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toLE.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (CompleteSemilatticeInf.toPartialOrder.{u1} (Subgroup.{u1} G _inst_1) (CompleteLattice.toCompleteSemilatticeInf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instCompleteLatticeSubgroup.{u1} G _inst_1))))) K L) -> (Eq.{1} Nat (HMul.hMul.{0, 0, 0} Nat Nat Nat (instHMul.{0} Nat instMulNat) (Subgroup.relindex.{u1} G _inst_1 H K) (Subgroup.relindex.{u1} G _inst_1 K L)) (Subgroup.relindex.{u1} G _inst_1 H L))
 Case conversion may be inaccurate. Consider using '#align subgroup.relindex_mul_relindex Subgroup.relindex_mul_relindexₓ'. -/
@@ -255,7 +255,7 @@ variable {H K}
 
 /- warning: subgroup.relindex_dvd_of_le_left -> Subgroup.relindex_dvd_of_le_left is a dubious translation:
 lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1} (L : Subgroup.{u1} G _inst_1), (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toLE.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (SetLike.partialOrder.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)))) H K) -> (Dvd.Dvd.{0} Nat Nat.hasDvd (Subgroup.relindex.{u1} G _inst_1 K L) (Subgroup.relindex.{u1} G _inst_1 H L))
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1} (L : Subgroup.{u1} G _inst_1), (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toHasLe.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (SetLike.partialOrder.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)))) H K) -> (Dvd.Dvd.{0} Nat Nat.hasDvd (Subgroup.relindex.{u1} G _inst_1 K L) (Subgroup.relindex.{u1} G _inst_1 H L))
 but is expected to have type
   forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1} (L : Subgroup.{u1} G _inst_1), (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toLE.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (CompleteSemilatticeInf.toPartialOrder.{u1} (Subgroup.{u1} G _inst_1) (CompleteLattice.toCompleteSemilatticeInf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instCompleteLatticeSubgroup.{u1} G _inst_1))))) H K) -> (Dvd.dvd.{0} Nat Nat.instDvdNat (Subgroup.relindex.{u1} G _inst_1 K L) (Subgroup.relindex.{u1} G _inst_1 H L))
 Case conversion may be inaccurate. Consider using '#align subgroup.relindex_dvd_of_le_left Subgroup.relindex_dvd_of_le_leftₓ'. -/
@@ -496,7 +496,7 @@ theorem nat_card_dvd_of_injective {G H : Type _} [Group G] [Group H] (f : G →*
 
 /- warning: subgroup.nat_card_dvd_of_le -> Subgroup.nat_card_dvd_of_le is a dubious translation:
 lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) (K : Subgroup.{u1} G _inst_1), (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toLE.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (SetLike.partialOrder.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)))) H K) -> (Dvd.Dvd.{0} Nat Nat.hasDvd (Nat.card.{u1} (coeSort.{succ u1, succ (succ u1)} (Subgroup.{u1} G _inst_1) Type.{u1} (SetLike.hasCoeToSort.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)) H)) (Nat.card.{u1} (coeSort.{succ u1, succ (succ u1)} (Subgroup.{u1} G _inst_1) Type.{u1} (SetLike.hasCoeToSort.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)) K)))
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) (K : Subgroup.{u1} G _inst_1), (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toHasLe.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (SetLike.partialOrder.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)))) H K) -> (Dvd.Dvd.{0} Nat Nat.hasDvd (Nat.card.{u1} (coeSort.{succ u1, succ (succ u1)} (Subgroup.{u1} G _inst_1) Type.{u1} (SetLike.hasCoeToSort.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)) H)) (Nat.card.{u1} (coeSort.{succ u1, succ (succ u1)} (Subgroup.{u1} G _inst_1) Type.{u1} (SetLike.hasCoeToSort.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)) K)))
 but is expected to have type
   forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) (K : Subgroup.{u1} G _inst_1), (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toLE.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (CompleteSemilatticeInf.toPartialOrder.{u1} (Subgroup.{u1} G _inst_1) (CompleteLattice.toCompleteSemilatticeInf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instCompleteLatticeSubgroup.{u1} G _inst_1))))) H K) -> (Dvd.dvd.{0} Nat Nat.instDvdNat (Nat.card.{u1} (Subtype.{succ u1} G (fun (x : G) => Membership.mem.{u1, u1} G (Subgroup.{u1} G _inst_1) (SetLike.instMembership.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.instSetLikeSubgroup.{u1} G _inst_1)) x H))) (Nat.card.{u1} (Subtype.{succ u1} G (fun (x : G) => Membership.mem.{u1, u1} G (Subgroup.{u1} G _inst_1) (SetLike.instMembership.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.instSetLikeSubgroup.{u1} G _inst_1)) x K))))
 Case conversion may be inaccurate. Consider using '#align subgroup.nat_card_dvd_of_le Subgroup.nat_card_dvd_of_leₓ'. -/
@@ -564,7 +564,7 @@ theorem index_map_dvd {G' : Type _} [Group G'] {f : G →* G'} (hf : Function.Su
 
 /- warning: subgroup.dvd_index_map -> Subgroup.dvd_index_map is a dubious translation:
 lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) {G' : Type.{u2}} [_inst_2 : Group.{u2} G'] {f : MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))}, (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toLE.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (SetLike.partialOrder.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)))) (MonoidHom.ker.{u1, u2} G _inst_1 G' (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) f) H) -> (Dvd.Dvd.{0} Nat Nat.hasDvd (Subgroup.index.{u1} G _inst_1 H) (Subgroup.index.{u2} G' _inst_2 (Subgroup.map.{u1, u2} G _inst_1 G' _inst_2 f H)))
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) {G' : Type.{u2}} [_inst_2 : Group.{u2} G'] {f : MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))}, (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toHasLe.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (SetLike.partialOrder.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)))) (MonoidHom.ker.{u1, u2} G _inst_1 G' (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) f) H) -> (Dvd.Dvd.{0} Nat Nat.hasDvd (Subgroup.index.{u1} G _inst_1 H) (Subgroup.index.{u2} G' _inst_2 (Subgroup.map.{u1, u2} G _inst_1 G' _inst_2 f H)))
 but is expected to have type
   forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) {G' : Type.{u2}} [_inst_2 : Group.{u2} G'] {f : MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))}, (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toLE.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (CompleteSemilatticeInf.toPartialOrder.{u1} (Subgroup.{u1} G _inst_1) (CompleteLattice.toCompleteSemilatticeInf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instCompleteLatticeSubgroup.{u1} G _inst_1))))) (MonoidHom.ker.{u1, u2} G _inst_1 G' (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) f) H) -> (Dvd.dvd.{0} Nat Nat.instDvdNat (Subgroup.index.{u1} G _inst_1 H) (Subgroup.index.{u2} G' _inst_2 (Subgroup.map.{u1, u2} G _inst_1 G' _inst_2 f H)))
 Case conversion may be inaccurate. Consider using '#align subgroup.dvd_index_map Subgroup.dvd_index_mapₓ'. -/
@@ -578,7 +578,7 @@ theorem dvd_index_map {G' : Type _} [Group G'] {f : G →* G'} (hf : f.ker ≤ H
 
 /- warning: subgroup.index_map_eq -> Subgroup.index_map_eq is a dubious translation:
 lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) {G' : Type.{u2}} [_inst_2 : Group.{u2} G'] {f : MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))}, (Function.Surjective.{succ u1, succ u2} G G' (coeFn.{max (succ u2) (succ u1), max (succ u1) (succ u2)} (MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) (fun (_x : MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) => G -> G') (MonoidHom.hasCoeToFun.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) f)) -> (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toLE.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (SetLike.partialOrder.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)))) (MonoidHom.ker.{u1, u2} G _inst_1 G' (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) f) H) -> (Eq.{1} Nat (Subgroup.index.{u2} G' _inst_2 (Subgroup.map.{u1, u2} G _inst_1 G' _inst_2 f H)) (Subgroup.index.{u1} G _inst_1 H))
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) {G' : Type.{u2}} [_inst_2 : Group.{u2} G'] {f : MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))}, (Function.Surjective.{succ u1, succ u2} G G' (coeFn.{max (succ u2) (succ u1), max (succ u1) (succ u2)} (MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) (fun (_x : MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) => G -> G') (MonoidHom.hasCoeToFun.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) f)) -> (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toHasLe.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (SetLike.partialOrder.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)))) (MonoidHom.ker.{u1, u2} G _inst_1 G' (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) f) H) -> (Eq.{1} Nat (Subgroup.index.{u2} G' _inst_2 (Subgroup.map.{u1, u2} G _inst_1 G' _inst_2 f H)) (Subgroup.index.{u1} G _inst_1 H))
 but is expected to have type
   forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) {G' : Type.{u2}} [_inst_2 : Group.{u2} G'] {f : MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))}, (Function.Surjective.{succ u1, succ u2} G G' (FunLike.coe.{max (succ u1) (succ u2), succ u1, succ u2} (MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) G (fun (_x : G) => (fun (x._@.Mathlib.Algebra.Hom.Group._hyg.2391 : G) => G') _x) (MulHomClass.toFunLike.{max u1 u2, u1, u2} (MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) G G' (MulOneClass.toMul.{u1} G (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) (MulOneClass.toMul.{u2} G' (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) (MonoidHomClass.toMulHomClass.{max u1 u2, u1, u2} (MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (MonoidHom.monoidHomClass.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))))) f)) -> (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toLE.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (CompleteSemilatticeInf.toPartialOrder.{u1} (Subgroup.{u1} G _inst_1) (CompleteLattice.toCompleteSemilatticeInf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instCompleteLatticeSubgroup.{u1} G _inst_1))))) (MonoidHom.ker.{u1, u2} G _inst_1 G' (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) f) H) -> (Eq.{1} Nat (Subgroup.index.{u2} G' _inst_2 (Subgroup.map.{u1, u2} G _inst_1 G' _inst_2 f H)) (Subgroup.index.{u1} G _inst_1 H))
 Case conversion may be inaccurate. Consider using '#align subgroup.index_map_eq Subgroup.index_map_eqₓ'. -/
@@ -623,7 +623,7 @@ variable {H K L}
 
 /- warning: subgroup.relindex_eq_zero_of_le_left -> Subgroup.relindex_eq_zero_of_le_left is a dubious translation:
 lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1} {L : Subgroup.{u1} G _inst_1}, (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toLE.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (SetLike.partialOrder.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)))) H K) -> (Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 K L) (OfNat.ofNat.{0} Nat 0 (OfNat.mk.{0} Nat 0 (Zero.zero.{0} Nat Nat.hasZero)))) -> (Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 H L) (OfNat.ofNat.{0} Nat 0 (OfNat.mk.{0} Nat 0 (Zero.zero.{0} Nat Nat.hasZero))))
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1} {L : Subgroup.{u1} G _inst_1}, (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toHasLe.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (SetLike.partialOrder.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)))) H K) -> (Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 K L) (OfNat.ofNat.{0} Nat 0 (OfNat.mk.{0} Nat 0 (Zero.zero.{0} Nat Nat.hasZero)))) -> (Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 H L) (OfNat.ofNat.{0} Nat 0 (OfNat.mk.{0} Nat 0 (Zero.zero.{0} Nat Nat.hasZero))))
 but is expected to have type
   forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1} {L : Subgroup.{u1} G _inst_1}, (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toLE.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (CompleteSemilatticeInf.toPartialOrder.{u1} (Subgroup.{u1} G _inst_1) (CompleteLattice.toCompleteSemilatticeInf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instCompleteLatticeSubgroup.{u1} G _inst_1))))) H K) -> (Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 K L) (OfNat.ofNat.{0} Nat 0 (instOfNatNat 0))) -> (Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 H L) (OfNat.ofNat.{0} Nat 0 (instOfNatNat 0)))
 Case conversion may be inaccurate. Consider using '#align subgroup.relindex_eq_zero_of_le_left Subgroup.relindex_eq_zero_of_le_leftₓ'. -/
@@ -635,7 +635,7 @@ theorem relindex_eq_zero_of_le_left (hHK : H ≤ K) (hKL : K.relindex L = 0) : H
 
 /- warning: subgroup.relindex_eq_zero_of_le_right -> Subgroup.relindex_eq_zero_of_le_right is a dubious translation:
 lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1} {L : Subgroup.{u1} G _inst_1}, (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toLE.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (SetLike.partialOrder.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)))) K L) -> (Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 H K) (OfNat.ofNat.{0} Nat 0 (OfNat.mk.{0} Nat 0 (Zero.zero.{0} Nat Nat.hasZero)))) -> (Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 H L) (OfNat.ofNat.{0} Nat 0 (OfNat.mk.{0} Nat 0 (Zero.zero.{0} Nat Nat.hasZero))))
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1} {L : Subgroup.{u1} G _inst_1}, (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toHasLe.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (SetLike.partialOrder.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)))) K L) -> (Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 H K) (OfNat.ofNat.{0} Nat 0 (OfNat.mk.{0} Nat 0 (Zero.zero.{0} Nat Nat.hasZero)))) -> (Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 H L) (OfNat.ofNat.{0} Nat 0 (OfNat.mk.{0} Nat 0 (Zero.zero.{0} Nat Nat.hasZero))))
 but is expected to have type
   forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1} {L : Subgroup.{u1} G _inst_1}, (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toLE.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (CompleteSemilatticeInf.toPartialOrder.{u1} (Subgroup.{u1} G _inst_1) (CompleteLattice.toCompleteSemilatticeInf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instCompleteLatticeSubgroup.{u1} G _inst_1))))) K L) -> (Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 H K) (OfNat.ofNat.{0} Nat 0 (instOfNatNat 0))) -> (Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 H L) (OfNat.ofNat.{0} Nat 0 (instOfNatNat 0)))
 Case conversion may be inaccurate. Consider using '#align subgroup.relindex_eq_zero_of_le_right Subgroup.relindex_eq_zero_of_le_rightₓ'. -/
@@ -655,7 +655,7 @@ theorem index_eq_zero_of_relindex_eq_zero (h : H.relindex K = 0) : H.index = 0 :
 
 /- warning: subgroup.relindex_le_of_le_left -> Subgroup.relindex_le_of_le_left is a dubious translation:
 lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1} {L : Subgroup.{u1} G _inst_1}, (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toLE.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (SetLike.partialOrder.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)))) H K) -> (Ne.{1} Nat (Subgroup.relindex.{u1} G _inst_1 H L) (OfNat.ofNat.{0} Nat 0 (OfNat.mk.{0} Nat 0 (Zero.zero.{0} Nat Nat.hasZero)))) -> (LE.le.{0} Nat Nat.hasLe (Subgroup.relindex.{u1} G _inst_1 K L) (Subgroup.relindex.{u1} G _inst_1 H L))
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1} {L : Subgroup.{u1} G _inst_1}, (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toHasLe.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (SetLike.partialOrder.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)))) H K) -> (Ne.{1} Nat (Subgroup.relindex.{u1} G _inst_1 H L) (OfNat.ofNat.{0} Nat 0 (OfNat.mk.{0} Nat 0 (Zero.zero.{0} Nat Nat.hasZero)))) -> (LE.le.{0} Nat Nat.hasLe (Subgroup.relindex.{u1} G _inst_1 K L) (Subgroup.relindex.{u1} G _inst_1 H L))
 but is expected to have type
   forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1} {L : Subgroup.{u1} G _inst_1}, (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toLE.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (CompleteSemilatticeInf.toPartialOrder.{u1} (Subgroup.{u1} G _inst_1) (CompleteLattice.toCompleteSemilatticeInf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instCompleteLatticeSubgroup.{u1} G _inst_1))))) H K) -> (Ne.{1} Nat (Subgroup.relindex.{u1} G _inst_1 H L) (OfNat.ofNat.{0} Nat 0 (instOfNatNat 0))) -> (LE.le.{0} Nat instLENat (Subgroup.relindex.{u1} G _inst_1 K L) (Subgroup.relindex.{u1} G _inst_1 H L))
 Case conversion may be inaccurate. Consider using '#align subgroup.relindex_le_of_le_left Subgroup.relindex_le_of_le_leftₓ'. -/
@@ -668,7 +668,7 @@ theorem relindex_le_of_le_left (hHK : H ≤ K) (hHL : H.relindex L ≠ 0) :
 
 /- warning: subgroup.relindex_le_of_le_right -> Subgroup.relindex_le_of_le_right is a dubious translation:
 lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1} {L : Subgroup.{u1} G _inst_1}, (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toLE.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (SetLike.partialOrder.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)))) K L) -> (Ne.{1} Nat (Subgroup.relindex.{u1} G _inst_1 H L) (OfNat.ofNat.{0} Nat 0 (OfNat.mk.{0} Nat 0 (Zero.zero.{0} Nat Nat.hasZero)))) -> (LE.le.{0} Nat Nat.hasLe (Subgroup.relindex.{u1} G _inst_1 H K) (Subgroup.relindex.{u1} G _inst_1 H L))
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1} {L : Subgroup.{u1} G _inst_1}, (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toHasLe.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (SetLike.partialOrder.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)))) K L) -> (Ne.{1} Nat (Subgroup.relindex.{u1} G _inst_1 H L) (OfNat.ofNat.{0} Nat 0 (OfNat.mk.{0} Nat 0 (Zero.zero.{0} Nat Nat.hasZero)))) -> (LE.le.{0} Nat Nat.hasLe (Subgroup.relindex.{u1} G _inst_1 H K) (Subgroup.relindex.{u1} G _inst_1 H L))
 but is expected to have type
   forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1} {L : Subgroup.{u1} G _inst_1}, (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toLE.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (CompleteSemilatticeInf.toPartialOrder.{u1} (Subgroup.{u1} G _inst_1) (CompleteLattice.toCompleteSemilatticeInf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instCompleteLatticeSubgroup.{u1} G _inst_1))))) K L) -> (Ne.{1} Nat (Subgroup.relindex.{u1} G _inst_1 H L) (OfNat.ofNat.{0} Nat 0 (instOfNatNat 0))) -> (LE.le.{0} Nat instLENat (Subgroup.relindex.{u1} G _inst_1 H K) (Subgroup.relindex.{u1} G _inst_1 H L))
 Case conversion may be inaccurate. Consider using '#align subgroup.relindex_le_of_le_right Subgroup.relindex_le_of_le_rightₓ'. -/
@@ -809,7 +809,7 @@ theorem index_eq_one : H.index = 1 ↔ H = ⊤ :=
 
 /- warning: subgroup.relindex_eq_one -> Subgroup.relindex_eq_one is a dubious translation:
 lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1}, Iff (Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 H K) (OfNat.ofNat.{0} Nat 1 (OfNat.mk.{0} Nat 1 (One.one.{0} Nat Nat.hasOne)))) (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toLE.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (SetLike.partialOrder.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)))) K H)
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1}, Iff (Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 H K) (OfNat.ofNat.{0} Nat 1 (OfNat.mk.{0} Nat 1 (One.one.{0} Nat Nat.hasOne)))) (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toHasLe.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (SetLike.partialOrder.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)))) K H)
 but is expected to have type
   forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1}, Iff (Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 H K) (OfNat.ofNat.{0} Nat 1 (instOfNatNat 1))) (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toLE.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (CompleteSemilatticeInf.toPartialOrder.{u1} (Subgroup.{u1} G _inst_1) (CompleteLattice.toCompleteSemilatticeInf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instCompleteLatticeSubgroup.{u1} G _inst_1))))) K H)
 Case conversion may be inaccurate. Consider using '#align subgroup.relindex_eq_one Subgroup.relindex_eq_oneₓ'. -/
@@ -926,7 +926,7 @@ variable {H K}
 
 /- warning: subgroup.finite_index_of_le -> Subgroup.finiteIndex_of_le is a dubious translation:
 lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1} [_inst_2 : Subgroup.FiniteIndex.{u1} G _inst_1 H], (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toLE.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (SetLike.partialOrder.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)))) H K) -> (Subgroup.FiniteIndex.{u1} G _inst_1 K)
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1} [_inst_2 : Subgroup.FiniteIndex.{u1} G _inst_1 H], (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toHasLe.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (SetLike.partialOrder.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)))) H K) -> (Subgroup.FiniteIndex.{u1} G _inst_1 K)
 but is expected to have type
   forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1} [_inst_2 : Subgroup.FiniteIndex.{u1} G _inst_1 H], (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toLE.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (CompleteSemilatticeInf.toPartialOrder.{u1} (Subgroup.{u1} G _inst_1) (CompleteLattice.toCompleteSemilatticeInf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instCompleteLatticeSubgroup.{u1} G _inst_1))))) H K) -> (Subgroup.FiniteIndex.{u1} G _inst_1 K)
 Case conversion may be inaccurate. Consider using '#align subgroup.finite_index_of_le Subgroup.finiteIndex_of_leₓ'. -/

mathlib commit https://github.com/leanprover-community/mathlib/commit/0b9eaaa7686280fad8cce467f5c3c57ee6ce77f8

@@ -963,7 +963,7 @@ instance finiteIndex_normalCore [H.FiniteIndex] : H.normalCore.FiniteIndex :=
 variable (G)
 
 #print Subgroup.finiteIndex_center /-
-instance finiteIndex_center [Finite (commutatorSet G)] [Group.Fg G] : FiniteIndex (center G) :=
+instance finiteIndex_center [Finite (commutatorSet G)] [Group.FG G] : FiniteIndex (center G) :=
   by
   obtain ⟨S, -, hS⟩ := Group.rank_spec G
   exact ⟨mt (Finite.card_eq_zero_of_embedding (quotient_center_embedding hS)) finite.card_pos.ne'⟩
@@ -971,7 +971,7 @@ instance finiteIndex_center [Finite (commutatorSet G)] [Group.Fg G] : FiniteInde
 -/
 
 #print Subgroup.index_center_le_pow /-
-theorem index_center_le_pow [Finite (commutatorSet G)] [Group.Fg G] :
+theorem index_center_le_pow [Finite (commutatorSet G)] [Group.FG G] :
     (center G).index ≤ Nat.card (commutatorSet G) ^ Group.rank G :=
   by
   obtain ⟨S, hS1, hS2⟩ := Group.rank_spec G

mathlib commit https://github.com/leanprover-community/mathlib/commit/e3fb84046afd187b710170887195d50bada934ee

@@ -749,48 +749,48 @@ theorem index_inf_le : (H ⊓ K).index ≤ H.index * K.index := by
 #align subgroup.index_inf_le Subgroup.index_inf_le
 #align add_subgroup.index_inf_le AddSubgroup.index_inf_le
 
-#print Subgroup.relindex_infᵢ_ne_zero /-
+#print Subgroup.relindex_iInf_ne_zero /-
 @[to_additive]
-theorem relindex_infᵢ_ne_zero {ι : Type _} [hι : Finite ι] {f : ι → Subgroup G}
+theorem relindex_iInf_ne_zero {ι : Type _} [hι : Finite ι] {f : ι → Subgroup G}
     (hf : ∀ i, (f i).relindex L ≠ 0) : (⨅ i, f i).relindex L ≠ 0 :=
   haveI := Fintype.ofFinite ι
   (finset.prod_ne_zero_iff.mpr fun i hi => hf i) ∘
     nat.card_pi.symm.trans ∘
       Finite.card_eq_zero_of_embedding (quotient_infi_subgroup_of_embedding f L)
-#align subgroup.relindex_infi_ne_zero Subgroup.relindex_infᵢ_ne_zero
-#align add_subgroup.relindex_infi_ne_zero AddSubgroup.relindex_infᵢ_ne_zero
+#align subgroup.relindex_infi_ne_zero Subgroup.relindex_iInf_ne_zero
+#align add_subgroup.relindex_infi_ne_zero AddSubgroup.relindex_iInf_ne_zero
 -/
 
-#print Subgroup.relindex_infᵢ_le /-
+#print Subgroup.relindex_iInf_le /-
 @[to_additive]
-theorem relindex_infᵢ_le {ι : Type _} [Fintype ι] (f : ι → Subgroup G) :
+theorem relindex_iInf_le {ι : Type _} [Fintype ι] (f : ι → Subgroup G) :
     (⨅ i, f i).relindex L ≤ ∏ i, (f i).relindex L :=
   le_of_le_of_eq
-    (Finite.card_le_of_embedding' (quotientInfᵢSubgroupOfEmbedding f L) fun h =>
+    (Finite.card_le_of_embedding' (quotientiInfSubgroupOfEmbedding f L) fun h =>
       let ⟨i, hi, h⟩ := Finset.prod_eq_zero_iff.mp (Nat.card_pi.symm.trans h)
-      relindex_eq_zero_of_le_left (infᵢ_le f i) h)
+      relindex_eq_zero_of_le_left (iInf_le f i) h)
     Nat.card_pi
-#align subgroup.relindex_infi_le Subgroup.relindex_infᵢ_le
-#align add_subgroup.relindex_infi_le AddSubgroup.relindex_infᵢ_le
+#align subgroup.relindex_infi_le Subgroup.relindex_iInf_le
+#align add_subgroup.relindex_infi_le AddSubgroup.relindex_iInf_le
 -/
 
-#print Subgroup.index_infᵢ_ne_zero /-
+#print Subgroup.index_iInf_ne_zero /-
 @[to_additive]
-theorem index_infᵢ_ne_zero {ι : Type _} [Finite ι] {f : ι → Subgroup G}
+theorem index_iInf_ne_zero {ι : Type _} [Finite ι] {f : ι → Subgroup G}
     (hf : ∀ i, (f i).index ≠ 0) : (⨅ i, f i).index ≠ 0 :=
   by
   simp_rw [← relindex_top_right] at hf⊢
   exact relindex_infi_ne_zero hf
-#align subgroup.index_infi_ne_zero Subgroup.index_infᵢ_ne_zero
-#align add_subgroup.index_infi_ne_zero AddSubgroup.index_infᵢ_ne_zero
+#align subgroup.index_infi_ne_zero Subgroup.index_iInf_ne_zero
+#align add_subgroup.index_infi_ne_zero AddSubgroup.index_iInf_ne_zero
 -/
 
-#print Subgroup.index_infᵢ_le /-
+#print Subgroup.index_iInf_le /-
 @[to_additive]
-theorem index_infᵢ_le {ι : Type _} [Fintype ι] (f : ι → Subgroup G) :
+theorem index_iInf_le {ι : Type _} [Fintype ι] (f : ι → Subgroup G) :
     (⨅ i, f i).index ≤ ∏ i, (f i).index := by simp_rw [← relindex_top_right, relindex_infi_le]
-#align subgroup.index_infi_le Subgroup.index_infᵢ_le
-#align add_subgroup.index_infi_le AddSubgroup.index_infᵢ_le
+#align subgroup.index_infi_le Subgroup.index_iInf_le
+#align add_subgroup.index_infi_le AddSubgroup.index_iInf_le
 -/
 
 /- warning: subgroup.index_eq_one -> Subgroup.index_eq_one is a dubious translation:

mathlib commit https://github.com/leanprover-community/mathlib/commit/3180fab693e2cee3bff62675571264cb8778b212

@@ -71,7 +71,7 @@ noncomputable def relindex : ℕ :=
 lean 3 declaration is
   forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) {G' : Type.{u2}} [_inst_2 : Group.{u2} G'] {f : MonoidHom.{u2, u1} G' G (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))}, (Function.Surjective.{succ u2, succ u1} G' G (coeFn.{max (succ u1) (succ u2), max (succ u2) (succ u1)} (MonoidHom.{u2, u1} G' G (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) (fun (_x : MonoidHom.{u2, u1} G' G (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) => G' -> G) (MonoidHom.hasCoeToFun.{u2, u1} G' G (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) f)) -> (Eq.{1} Nat (Subgroup.index.{u2} G' _inst_2 (Subgroup.comap.{u2, u1} G' _inst_2 G _inst_1 f H)) (Subgroup.index.{u1} G _inst_1 H))
 but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) {G' : Type.{u2}} [_inst_2 : Group.{u2} G'] {f : MonoidHom.{u2, u1} G' G (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))}, (Function.Surjective.{succ u2, succ u1} G' G (FunLike.coe.{max (succ u1) (succ u2), succ u2, succ u1} (MonoidHom.{u2, u1} G' G (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) G' (fun (_x : G') => (fun (x._@.Mathlib.Algebra.Hom.Group._hyg.2372 : G') => G) _x) (MulHomClass.toFunLike.{max u1 u2, u2, u1} (MonoidHom.{u2, u1} G' G (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) G' G (MulOneClass.toMul.{u2} G' (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) (MulOneClass.toMul.{u1} G (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) (MonoidHomClass.toMulHomClass.{max u1 u2, u2, u1} (MonoidHom.{u2, u1} G' G (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) G' G (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (MonoidHom.monoidHomClass.{u2, u1} G' G (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))))) f)) -> (Eq.{1} Nat (Subgroup.index.{u2} G' _inst_2 (Subgroup.comap.{u2, u1} G' _inst_2 G _inst_1 f H)) (Subgroup.index.{u1} G _inst_1 H))
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) {G' : Type.{u2}} [_inst_2 : Group.{u2} G'] {f : MonoidHom.{u2, u1} G' G (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))}, (Function.Surjective.{succ u2, succ u1} G' G (FunLike.coe.{max (succ u1) (succ u2), succ u2, succ u1} (MonoidHom.{u2, u1} G' G (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) G' (fun (_x : G') => (fun (x._@.Mathlib.Algebra.Hom.Group._hyg.2391 : G') => G) _x) (MulHomClass.toFunLike.{max u1 u2, u2, u1} (MonoidHom.{u2, u1} G' G (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) G' G (MulOneClass.toMul.{u2} G' (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) (MulOneClass.toMul.{u1} G (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) (MonoidHomClass.toMulHomClass.{max u1 u2, u2, u1} (MonoidHom.{u2, u1} G' G (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) G' G (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (MonoidHom.monoidHomClass.{u2, u1} G' G (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))))) f)) -> (Eq.{1} Nat (Subgroup.index.{u2} G' _inst_2 (Subgroup.comap.{u2, u1} G' _inst_2 G _inst_1 f H)) (Subgroup.index.{u1} G _inst_1 H))
 Case conversion may be inaccurate. Consider using '#align subgroup.index_comap_of_surjective Subgroup.index_comap_of_surjectiveₓ'. -/
 @[to_additive]
 theorem index_comap_of_surjective {G' : Type _} [Group G'] {f : G' →* G}
@@ -440,7 +440,7 @@ theorem relindex_self : H.relindex H = 1 := by rw [relindex, subgroup_of_self, i
 lean 3 declaration is
   forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Type.{u2}} [_inst_2 : Group.{u2} H] (f : MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))), Eq.{1} Nat (Subgroup.index.{u1} G _inst_1 (MonoidHom.ker.{u1, u2} G _inst_1 H (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2))) f)) (Nat.card.{u2} (coeSort.{succ u2, succ (succ u2)} (Set.{u2} H) Type.{u2} (Set.hasCoeToSort.{u2} H) (Set.range.{u2, succ u1} H G (coeFn.{max (succ u2) (succ u1), max (succ u1) (succ u2)} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) (fun (_x : MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) => G -> H) (MonoidHom.hasCoeToFun.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) f))))
 but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Type.{u2}} [_inst_2 : Group.{u2} H] (f : MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))), Eq.{1} Nat (Subgroup.index.{u1} G _inst_1 (MonoidHom.ker.{u1, u2} G _inst_1 H (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2))) f)) (Nat.card.{u2} (Set.Elem.{u2} H (Set.range.{u2, succ u1} H G (FunLike.coe.{max (succ u1) (succ u2), succ u1, succ u2} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) G (fun (_x : G) => (fun (x._@.Mathlib.Algebra.Hom.Group._hyg.2372 : G) => H) _x) (MulHomClass.toFunLike.{max u1 u2, u1, u2} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) G H (MulOneClass.toMul.{u1} G (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) (MulOneClass.toMul.{u2} H (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) (MonoidHomClass.toMulHomClass.{max u1 u2, u1, u2} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2))) (MonoidHom.monoidHomClass.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))))) f))))
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Type.{u2}} [_inst_2 : Group.{u2} H] (f : MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))), Eq.{1} Nat (Subgroup.index.{u1} G _inst_1 (MonoidHom.ker.{u1, u2} G _inst_1 H (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2))) f)) (Nat.card.{u2} (Set.Elem.{u2} H (Set.range.{u2, succ u1} H G (FunLike.coe.{max (succ u1) (succ u2), succ u1, succ u2} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) G (fun (_x : G) => (fun (x._@.Mathlib.Algebra.Hom.Group._hyg.2391 : G) => H) _x) (MulHomClass.toFunLike.{max u1 u2, u1, u2} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) G H (MulOneClass.toMul.{u1} G (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) (MulOneClass.toMul.{u2} H (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) (MonoidHomClass.toMulHomClass.{max u1 u2, u1, u2} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2))) (MonoidHom.monoidHomClass.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))))) f))))
 Case conversion may be inaccurate. Consider using '#align subgroup.index_ker Subgroup.index_kerₓ'. -/
 @[to_additive]
 theorem index_ker {H} [Group H] (f : G →* H) : f.ker.index = Nat.card (Set.range f) :=
@@ -454,7 +454,7 @@ theorem index_ker {H} [Group H] (f : G →* H) : f.ker.index = Nat.card (Set.ran
 lean 3 declaration is
   forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Type.{u2}} [_inst_2 : Group.{u2} H] (f : MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) (K : Subgroup.{u1} G _inst_1), Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 (MonoidHom.ker.{u1, u2} G _inst_1 H (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2))) f) K) (Nat.card.{u2} (coeSort.{succ u2, succ (succ u2)} (Set.{u2} H) Type.{u2} (Set.hasCoeToSort.{u2} H) (Set.image.{u1, u2} G H (coeFn.{max (succ u2) (succ u1), max (succ u1) (succ u2)} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) (fun (_x : MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) => G -> H) (MonoidHom.hasCoeToFun.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) f) ((fun (a : Type.{u1}) (b : Type.{u1}) [self : HasLiftT.{succ u1, succ u1} a b] => self.0) (Subgroup.{u1} G _inst_1) (Set.{u1} G) (HasLiftT.mk.{succ u1, succ u1} (Subgroup.{u1} G _inst_1) (Set.{u1} G) (CoeTCₓ.coe.{succ u1, succ u1} (Subgroup.{u1} G _inst_1) (Set.{u1} G) (SetLike.Set.hasCoeT.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)))) K))))
 but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Type.{u2}} [_inst_2 : Group.{u2} H] (f : MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) (K : Subgroup.{u1} G _inst_1), Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 (MonoidHom.ker.{u1, u2} G _inst_1 H (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2))) f) K) (Nat.card.{u2} (Set.Elem.{u2} H (Set.image.{u1, u2} G H (FunLike.coe.{max (succ u1) (succ u2), succ u1, succ u2} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) G (fun (_x : G) => (fun (x._@.Mathlib.Algebra.Hom.Group._hyg.2372 : G) => H) _x) (MulHomClass.toFunLike.{max u1 u2, u1, u2} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) G H (MulOneClass.toMul.{u1} G (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) (MulOneClass.toMul.{u2} H (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) (MonoidHomClass.toMulHomClass.{max u1 u2, u1, u2} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2))) (MonoidHom.monoidHomClass.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))))) f) (SetLike.coe.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.instSetLikeSubgroup.{u1} G _inst_1) K))))
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Type.{u2}} [_inst_2 : Group.{u2} H] (f : MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) (K : Subgroup.{u1} G _inst_1), Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 (MonoidHom.ker.{u1, u2} G _inst_1 H (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2))) f) K) (Nat.card.{u2} (Set.Elem.{u2} H (Set.image.{u1, u2} G H (FunLike.coe.{max (succ u1) (succ u2), succ u1, succ u2} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) G (fun (_x : G) => (fun (x._@.Mathlib.Algebra.Hom.Group._hyg.2391 : G) => H) _x) (MulHomClass.toFunLike.{max u1 u2, u1, u2} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) G H (MulOneClass.toMul.{u1} G (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) (MulOneClass.toMul.{u2} H (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) (MonoidHomClass.toMulHomClass.{max u1 u2, u1, u2} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2))) (MonoidHom.monoidHomClass.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))))) f) (SetLike.coe.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.instSetLikeSubgroup.{u1} G _inst_1) K))))
 Case conversion may be inaccurate. Consider using '#align subgroup.relindex_ker Subgroup.relindex_kerₓ'. -/
 @[to_additive]
 theorem relindex_ker {H} [Group H] (f : G →* H) (K : Subgroup G) :
@@ -483,7 +483,7 @@ theorem card_mul_index : Nat.card H * H.index = Nat.card G :=
 lean 3 declaration is
   forall {G : Type.{u1}} {H : Type.{u2}} [_inst_2 : Group.{u1} G] [_inst_3 : Group.{u2} H] (f : MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_2))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_3)))), (Function.Injective.{succ u1, succ u2} G H (coeFn.{max (succ u2) (succ u1), max (succ u1) (succ u2)} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_2))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_3)))) (fun (_x : MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_2))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_3)))) => G -> H) (MonoidHom.hasCoeToFun.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_2))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_3)))) f)) -> (Dvd.Dvd.{0} Nat Nat.hasDvd (Nat.card.{u1} G) (Nat.card.{u2} H))
 but is expected to have type
-  forall {G : Type.{u2}} {H : Type.{u1}} [_inst_2 : Group.{u2} G] [_inst_3 : Group.{u1} H] (f : MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))), (Function.Injective.{succ u2, succ u1} G H (FunLike.coe.{max (succ u2) (succ u1), succ u2, succ u1} (MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) G (fun (_x : G) => (fun (x._@.Mathlib.Algebra.Hom.Group._hyg.2372 : G) => H) _x) (MulHomClass.toFunLike.{max u2 u1, u2, u1} (MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) G H (MulOneClass.toMul.{u2} G (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2)))) (MulOneClass.toMul.{u1} H (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) (MonoidHomClass.toMulHomClass.{max u2 u1, u2, u1} (MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3))) (MonoidHom.monoidHomClass.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))))) f)) -> (Dvd.dvd.{0} Nat Nat.instDvdNat (Nat.card.{u2} G) (Nat.card.{u1} H))
+  forall {G : Type.{u2}} {H : Type.{u1}} [_inst_2 : Group.{u2} G] [_inst_3 : Group.{u1} H] (f : MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))), (Function.Injective.{succ u2, succ u1} G H (FunLike.coe.{max (succ u2) (succ u1), succ u2, succ u1} (MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) G (fun (_x : G) => (fun (x._@.Mathlib.Algebra.Hom.Group._hyg.2391 : G) => H) _x) (MulHomClass.toFunLike.{max u2 u1, u2, u1} (MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) G H (MulOneClass.toMul.{u2} G (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2)))) (MulOneClass.toMul.{u1} H (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) (MonoidHomClass.toMulHomClass.{max u2 u1, u2, u1} (MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3))) (MonoidHom.monoidHomClass.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))))) f)) -> (Dvd.dvd.{0} Nat Nat.instDvdNat (Nat.card.{u2} G) (Nat.card.{u1} H))
 Case conversion may be inaccurate. Consider using '#align subgroup.nat_card_dvd_of_injective Subgroup.nat_card_dvd_of_injectiveₓ'. -/
 @[to_additive]
 theorem nat_card_dvd_of_injective {G H : Type _} [Group G] [Group H] (f : G →* H)
@@ -510,7 +510,7 @@ theorem nat_card_dvd_of_le (hHK : H ≤ K) : Nat.card H ∣ Nat.card K :=
 lean 3 declaration is
   forall {G : Type.{u1}} {H : Type.{u2}} [_inst_2 : Group.{u1} G] [_inst_3 : Group.{u2} H] (f : MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_2))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_3)))), (Function.Surjective.{succ u1, succ u2} G H (coeFn.{max (succ u2) (succ u1), max (succ u1) (succ u2)} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_2))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_3)))) (fun (_x : MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_2))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_3)))) => G -> H) (MonoidHom.hasCoeToFun.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_2))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_3)))) f)) -> (Dvd.Dvd.{0} Nat Nat.hasDvd (Nat.card.{u2} H) (Nat.card.{u1} G))
 but is expected to have type
-  forall {G : Type.{u2}} {H : Type.{u1}} [_inst_2 : Group.{u2} G] [_inst_3 : Group.{u1} H] (f : MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))), (Function.Surjective.{succ u2, succ u1} G H (FunLike.coe.{max (succ u2) (succ u1), succ u2, succ u1} (MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) G (fun (_x : G) => (fun (x._@.Mathlib.Algebra.Hom.Group._hyg.2372 : G) => H) _x) (MulHomClass.toFunLike.{max u2 u1, u2, u1} (MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) G H (MulOneClass.toMul.{u2} G (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2)))) (MulOneClass.toMul.{u1} H (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) (MonoidHomClass.toMulHomClass.{max u2 u1, u2, u1} (MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3))) (MonoidHom.monoidHomClass.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))))) f)) -> (Dvd.dvd.{0} Nat Nat.instDvdNat (Nat.card.{u1} H) (Nat.card.{u2} G))
+  forall {G : Type.{u2}} {H : Type.{u1}} [_inst_2 : Group.{u2} G] [_inst_3 : Group.{u1} H] (f : MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))), (Function.Surjective.{succ u2, succ u1} G H (FunLike.coe.{max (succ u2) (succ u1), succ u2, succ u1} (MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) G (fun (_x : G) => (fun (x._@.Mathlib.Algebra.Hom.Group._hyg.2391 : G) => H) _x) (MulHomClass.toFunLike.{max u2 u1, u2, u1} (MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) G H (MulOneClass.toMul.{u2} G (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2)))) (MulOneClass.toMul.{u1} H (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) (MonoidHomClass.toMulHomClass.{max u2 u1, u2, u1} (MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3))) (MonoidHom.monoidHomClass.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))))) f)) -> (Dvd.dvd.{0} Nat Nat.instDvdNat (Nat.card.{u1} H) (Nat.card.{u2} G))
 Case conversion may be inaccurate. Consider using '#align subgroup.nat_card_dvd_of_surjective Subgroup.nat_card_dvd_of_surjectiveₓ'. -/
 @[to_additive]
 theorem nat_card_dvd_of_surjective {G H : Type _} [Group G] [Group H] (f : G →* H)
@@ -525,7 +525,7 @@ theorem nat_card_dvd_of_surjective {G H : Type _} [Group G] [Group H] (f : G →
 lean 3 declaration is
   forall {G : Type.{u1}} {H : Type.{u2}} [_inst_2 : Group.{u1} G] [_inst_3 : Group.{u2} H] [_inst_4 : Fintype.{u1} G] [_inst_5 : Fintype.{u2} H] (f : MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_2))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_3)))), (Function.Surjective.{succ u1, succ u2} G H (coeFn.{max (succ u2) (succ u1), max (succ u1) (succ u2)} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_2))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_3)))) (fun (_x : MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_2))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_3)))) => G -> H) (MonoidHom.hasCoeToFun.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_2))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_3)))) f)) -> (Dvd.Dvd.{0} Nat Nat.hasDvd (Fintype.card.{u2} H _inst_5) (Fintype.card.{u1} G _inst_4))
 but is expected to have type
-  forall {G : Type.{u2}} {H : Type.{u1}} [_inst_2 : Group.{u2} G] [_inst_3 : Group.{u1} H] [_inst_4 : Fintype.{u2} G] [_inst_5 : Fintype.{u1} H] (f : MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))), (Function.Surjective.{succ u2, succ u1} G H (FunLike.coe.{max (succ u2) (succ u1), succ u2, succ u1} (MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) G (fun (_x : G) => (fun (x._@.Mathlib.Algebra.Hom.Group._hyg.2372 : G) => H) _x) (MulHomClass.toFunLike.{max u2 u1, u2, u1} (MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) G H (MulOneClass.toMul.{u2} G (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2)))) (MulOneClass.toMul.{u1} H (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) (MonoidHomClass.toMulHomClass.{max u2 u1, u2, u1} (MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3))) (MonoidHom.monoidHomClass.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))))) f)) -> (Dvd.dvd.{0} Nat Nat.instDvdNat (Fintype.card.{u1} H _inst_5) (Fintype.card.{u2} G _inst_4))
+  forall {G : Type.{u2}} {H : Type.{u1}} [_inst_2 : Group.{u2} G] [_inst_3 : Group.{u1} H] [_inst_4 : Fintype.{u2} G] [_inst_5 : Fintype.{u1} H] (f : MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))), (Function.Surjective.{succ u2, succ u1} G H (FunLike.coe.{max (succ u2) (succ u1), succ u2, succ u1} (MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) G (fun (_x : G) => (fun (x._@.Mathlib.Algebra.Hom.Group._hyg.2391 : G) => H) _x) (MulHomClass.toFunLike.{max u2 u1, u2, u1} (MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) G H (MulOneClass.toMul.{u2} G (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2)))) (MulOneClass.toMul.{u1} H (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) (MonoidHomClass.toMulHomClass.{max u2 u1, u2, u1} (MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3))) (MonoidHom.monoidHomClass.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))))) f)) -> (Dvd.dvd.{0} Nat Nat.instDvdNat (Fintype.card.{u1} H _inst_5) (Fintype.card.{u2} G _inst_4))
 Case conversion may be inaccurate. Consider using '#align subgroup.card_dvd_of_surjective Subgroup.card_dvd_of_surjectiveₓ'. -/
 @[to_additive]
 theorem card_dvd_of_surjective {G H : Type _} [Group G] [Group H] [Fintype G] [Fintype H]
@@ -551,7 +551,7 @@ theorem index_map {G' : Type _} [Group G'] (f : G →* G') :
 lean 3 declaration is
   forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) {G' : Type.{u2}} [_inst_2 : Group.{u2} G'] {f : MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))}, (Function.Surjective.{succ u1, succ u2} G G' (coeFn.{max (succ u2) (succ u1), max (succ u1) (succ u2)} (MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) (fun (_x : MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) => G -> G') (MonoidHom.hasCoeToFun.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) f)) -> (Dvd.Dvd.{0} Nat Nat.hasDvd (Subgroup.index.{u2} G' _inst_2 (Subgroup.map.{u1, u2} G _inst_1 G' _inst_2 f H)) (Subgroup.index.{u1} G _inst_1 H))
 but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) {G' : Type.{u2}} [_inst_2 : Group.{u2} G'] {f : MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))}, (Function.Surjective.{succ u1, succ u2} G G' (FunLike.coe.{max (succ u1) (succ u2), succ u1, succ u2} (MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) G (fun (_x : G) => (fun (x._@.Mathlib.Algebra.Hom.Group._hyg.2372 : G) => G') _x) (MulHomClass.toFunLike.{max u1 u2, u1, u2} (MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) G G' (MulOneClass.toMul.{u1} G (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) (MulOneClass.toMul.{u2} G' (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) (MonoidHomClass.toMulHomClass.{max u1 u2, u1, u2} (MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (MonoidHom.monoidHomClass.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))))) f)) -> (Dvd.dvd.{0} Nat Nat.instDvdNat (Subgroup.index.{u2} G' _inst_2 (Subgroup.map.{u1, u2} G _inst_1 G' _inst_2 f H)) (Subgroup.index.{u1} G _inst_1 H))
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) {G' : Type.{u2}} [_inst_2 : Group.{u2} G'] {f : MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))}, (Function.Surjective.{succ u1, succ u2} G G' (FunLike.coe.{max (succ u1) (succ u2), succ u1, succ u2} (MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) G (fun (_x : G) => (fun (x._@.Mathlib.Algebra.Hom.Group._hyg.2391 : G) => G') _x) (MulHomClass.toFunLike.{max u1 u2, u1, u2} (MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) G G' (MulOneClass.toMul.{u1} G (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) (MulOneClass.toMul.{u2} G' (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) (MonoidHomClass.toMulHomClass.{max u1 u2, u1, u2} (MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (MonoidHom.monoidHomClass.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))))) f)) -> (Dvd.dvd.{0} Nat Nat.instDvdNat (Subgroup.index.{u2} G' _inst_2 (Subgroup.map.{u1, u2} G _inst_1 G' _inst_2 f H)) (Subgroup.index.{u1} G _inst_1 H))
 Case conversion may be inaccurate. Consider using '#align subgroup.index_map_dvd Subgroup.index_map_dvdₓ'. -/
 @[to_additive]
 theorem index_map_dvd {G' : Type _} [Group G'] {f : G →* G'} (hf : Function.Surjective f) :
@@ -580,7 +580,7 @@ theorem dvd_index_map {G' : Type _} [Group G'] {f : G →* G'} (hf : f.ker ≤ H
 lean 3 declaration is
   forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) {G' : Type.{u2}} [_inst_2 : Group.{u2} G'] {f : MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))}, (Function.Surjective.{succ u1, succ u2} G G' (coeFn.{max (succ u2) (succ u1), max (succ u1) (succ u2)} (MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) (fun (_x : MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) => G -> G') (MonoidHom.hasCoeToFun.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) f)) -> (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toLE.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (SetLike.partialOrder.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)))) (MonoidHom.ker.{u1, u2} G _inst_1 G' (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) f) H) -> (Eq.{1} Nat (Subgroup.index.{u2} G' _inst_2 (Subgroup.map.{u1, u2} G _inst_1 G' _inst_2 f H)) (Subgroup.index.{u1} G _inst_1 H))
 but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) {G' : Type.{u2}} [_inst_2 : Group.{u2} G'] {f : MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))}, (Function.Surjective.{succ u1, succ u2} G G' (FunLike.coe.{max (succ u1) (succ u2), succ u1, succ u2} (MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) G (fun (_x : G) => (fun (x._@.Mathlib.Algebra.Hom.Group._hyg.2372 : G) => G') _x) (MulHomClass.toFunLike.{max u1 u2, u1, u2} (MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) G G' (MulOneClass.toMul.{u1} G (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) (MulOneClass.toMul.{u2} G' (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) (MonoidHomClass.toMulHomClass.{max u1 u2, u1, u2} (MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (MonoidHom.monoidHomClass.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))))) f)) -> (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toLE.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (CompleteSemilatticeInf.toPartialOrder.{u1} (Subgroup.{u1} G _inst_1) (CompleteLattice.toCompleteSemilatticeInf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instCompleteLatticeSubgroup.{u1} G _inst_1))))) (MonoidHom.ker.{u1, u2} G _inst_1 G' (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) f) H) -> (Eq.{1} Nat (Subgroup.index.{u2} G' _inst_2 (Subgroup.map.{u1, u2} G _inst_1 G' _inst_2 f H)) (Subgroup.index.{u1} G _inst_1 H))
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) {G' : Type.{u2}} [_inst_2 : Group.{u2} G'] {f : MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))}, (Function.Surjective.{succ u1, succ u2} G G' (FunLike.coe.{max (succ u1) (succ u2), succ u1, succ u2} (MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) G (fun (_x : G) => (fun (x._@.Mathlib.Algebra.Hom.Group._hyg.2391 : G) => G') _x) (MulHomClass.toFunLike.{max u1 u2, u1, u2} (MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) G G' (MulOneClass.toMul.{u1} G (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) (MulOneClass.toMul.{u2} G' (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) (MonoidHomClass.toMulHomClass.{max u1 u2, u1, u2} (MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (MonoidHom.monoidHomClass.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))))) f)) -> (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toLE.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (CompleteSemilatticeInf.toPartialOrder.{u1} (Subgroup.{u1} G _inst_1) (CompleteLattice.toCompleteSemilatticeInf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instCompleteLatticeSubgroup.{u1} G _inst_1))))) (MonoidHom.ker.{u1, u2} G _inst_1 G' (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) f) H) -> (Eq.{1} Nat (Subgroup.index.{u2} G' _inst_2 (Subgroup.map.{u1, u2} G _inst_1 G' _inst_2 f H)) (Subgroup.index.{u1} G _inst_1 H))
 Case conversion may be inaccurate. Consider using '#align subgroup.index_map_eq Subgroup.index_map_eqₓ'. -/
 @[to_additive]
 theorem index_map_eq {G' : Type _} [Group G'] {f : G →* G'} (hf1 : Function.Surjective f)

mathlib commit https://github.com/leanprover-community/mathlib/commit/38f16f960f5006c6c0c2bac7b0aba5273188f4e5

@@ -71,7 +71,7 @@ noncomputable def relindex : ℕ :=
 lean 3 declaration is
   forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) {G' : Type.{u2}} [_inst_2 : Group.{u2} G'] {f : MonoidHom.{u2, u1} G' G (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))}, (Function.Surjective.{succ u2, succ u1} G' G (coeFn.{max (succ u1) (succ u2), max (succ u2) (succ u1)} (MonoidHom.{u2, u1} G' G (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) (fun (_x : MonoidHom.{u2, u1} G' G (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) => G' -> G) (MonoidHom.hasCoeToFun.{u2, u1} G' G (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) f)) -> (Eq.{1} Nat (Subgroup.index.{u2} G' _inst_2 (Subgroup.comap.{u2, u1} G' _inst_2 G _inst_1 f H)) (Subgroup.index.{u1} G _inst_1 H))
 but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) {G' : Type.{u2}} [_inst_2 : Group.{u2} G'] {f : MonoidHom.{u2, u1} G' G (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))}, (Function.Surjective.{succ u2, succ u1} G' G (FunLike.coe.{max (succ u1) (succ u2), succ u2, succ u1} (MonoidHom.{u2, u1} G' G (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) G' (fun (_x : G') => (fun (x._@.Mathlib.Algebra.Hom.Group._hyg.2398 : G') => G) _x) (MulHomClass.toFunLike.{max u1 u2, u2, u1} (MonoidHom.{u2, u1} G' G (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) G' G (MulOneClass.toMul.{u2} G' (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) (MulOneClass.toMul.{u1} G (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) (MonoidHomClass.toMulHomClass.{max u1 u2, u2, u1} (MonoidHom.{u2, u1} G' G (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) G' G (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (MonoidHom.monoidHomClass.{u2, u1} G' G (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))))) f)) -> (Eq.{1} Nat (Subgroup.index.{u2} G' _inst_2 (Subgroup.comap.{u2, u1} G' _inst_2 G _inst_1 f H)) (Subgroup.index.{u1} G _inst_1 H))
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) {G' : Type.{u2}} [_inst_2 : Group.{u2} G'] {f : MonoidHom.{u2, u1} G' G (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))}, (Function.Surjective.{succ u2, succ u1} G' G (FunLike.coe.{max (succ u1) (succ u2), succ u2, succ u1} (MonoidHom.{u2, u1} G' G (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) G' (fun (_x : G') => (fun (x._@.Mathlib.Algebra.Hom.Group._hyg.2372 : G') => G) _x) (MulHomClass.toFunLike.{max u1 u2, u2, u1} (MonoidHom.{u2, u1} G' G (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) G' G (MulOneClass.toMul.{u2} G' (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) (MulOneClass.toMul.{u1} G (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) (MonoidHomClass.toMulHomClass.{max u1 u2, u2, u1} (MonoidHom.{u2, u1} G' G (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) G' G (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (MonoidHom.monoidHomClass.{u2, u1} G' G (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))))) f)) -> (Eq.{1} Nat (Subgroup.index.{u2} G' _inst_2 (Subgroup.comap.{u2, u1} G' _inst_2 G _inst_1 f H)) (Subgroup.index.{u1} G _inst_1 H))
 Case conversion may be inaccurate. Consider using '#align subgroup.index_comap_of_surjective Subgroup.index_comap_of_surjectiveₓ'. -/
 @[to_additive]
 theorem index_comap_of_surjective {G' : Type _} [Group G'] {f : G' →* G}
@@ -440,7 +440,7 @@ theorem relindex_self : H.relindex H = 1 := by rw [relindex, subgroup_of_self, i
 lean 3 declaration is
   forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Type.{u2}} [_inst_2 : Group.{u2} H] (f : MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))), Eq.{1} Nat (Subgroup.index.{u1} G _inst_1 (MonoidHom.ker.{u1, u2} G _inst_1 H (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2))) f)) (Nat.card.{u2} (coeSort.{succ u2, succ (succ u2)} (Set.{u2} H) Type.{u2} (Set.hasCoeToSort.{u2} H) (Set.range.{u2, succ u1} H G (coeFn.{max (succ u2) (succ u1), max (succ u1) (succ u2)} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) (fun (_x : MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) => G -> H) (MonoidHom.hasCoeToFun.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) f))))
 but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Type.{u2}} [_inst_2 : Group.{u2} H] (f : MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))), Eq.{1} Nat (Subgroup.index.{u1} G _inst_1 (MonoidHom.ker.{u1, u2} G _inst_1 H (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2))) f)) (Nat.card.{u2} (Set.Elem.{u2} H (Set.range.{u2, succ u1} H G (FunLike.coe.{max (succ u1) (succ u2), succ u1, succ u2} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) G (fun (_x : G) => (fun (x._@.Mathlib.Algebra.Hom.Group._hyg.2398 : G) => H) _x) (MulHomClass.toFunLike.{max u1 u2, u1, u2} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) G H (MulOneClass.toMul.{u1} G (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) (MulOneClass.toMul.{u2} H (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) (MonoidHomClass.toMulHomClass.{max u1 u2, u1, u2} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2))) (MonoidHom.monoidHomClass.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))))) f))))
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Type.{u2}} [_inst_2 : Group.{u2} H] (f : MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))), Eq.{1} Nat (Subgroup.index.{u1} G _inst_1 (MonoidHom.ker.{u1, u2} G _inst_1 H (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2))) f)) (Nat.card.{u2} (Set.Elem.{u2} H (Set.range.{u2, succ u1} H G (FunLike.coe.{max (succ u1) (succ u2), succ u1, succ u2} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) G (fun (_x : G) => (fun (x._@.Mathlib.Algebra.Hom.Group._hyg.2372 : G) => H) _x) (MulHomClass.toFunLike.{max u1 u2, u1, u2} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) G H (MulOneClass.toMul.{u1} G (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) (MulOneClass.toMul.{u2} H (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) (MonoidHomClass.toMulHomClass.{max u1 u2, u1, u2} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2))) (MonoidHom.monoidHomClass.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))))) f))))
 Case conversion may be inaccurate. Consider using '#align subgroup.index_ker Subgroup.index_kerₓ'. -/
 @[to_additive]
 theorem index_ker {H} [Group H] (f : G →* H) : f.ker.index = Nat.card (Set.range f) :=
@@ -454,7 +454,7 @@ theorem index_ker {H} [Group H] (f : G →* H) : f.ker.index = Nat.card (Set.ran
 lean 3 declaration is
   forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Type.{u2}} [_inst_2 : Group.{u2} H] (f : MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) (K : Subgroup.{u1} G _inst_1), Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 (MonoidHom.ker.{u1, u2} G _inst_1 H (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2))) f) K) (Nat.card.{u2} (coeSort.{succ u2, succ (succ u2)} (Set.{u2} H) Type.{u2} (Set.hasCoeToSort.{u2} H) (Set.image.{u1, u2} G H (coeFn.{max (succ u2) (succ u1), max (succ u1) (succ u2)} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) (fun (_x : MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) => G -> H) (MonoidHom.hasCoeToFun.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) f) ((fun (a : Type.{u1}) (b : Type.{u1}) [self : HasLiftT.{succ u1, succ u1} a b] => self.0) (Subgroup.{u1} G _inst_1) (Set.{u1} G) (HasLiftT.mk.{succ u1, succ u1} (Subgroup.{u1} G _inst_1) (Set.{u1} G) (CoeTCₓ.coe.{succ u1, succ u1} (Subgroup.{u1} G _inst_1) (Set.{u1} G) (SetLike.Set.hasCoeT.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)))) K))))
 but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Type.{u2}} [_inst_2 : Group.{u2} H] (f : MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) (K : Subgroup.{u1} G _inst_1), Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 (MonoidHom.ker.{u1, u2} G _inst_1 H (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2))) f) K) (Nat.card.{u2} (Set.Elem.{u2} H (Set.image.{u1, u2} G H (FunLike.coe.{max (succ u1) (succ u2), succ u1, succ u2} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) G (fun (_x : G) => (fun (x._@.Mathlib.Algebra.Hom.Group._hyg.2398 : G) => H) _x) (MulHomClass.toFunLike.{max u1 u2, u1, u2} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) G H (MulOneClass.toMul.{u1} G (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) (MulOneClass.toMul.{u2} H (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) (MonoidHomClass.toMulHomClass.{max u1 u2, u1, u2} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2))) (MonoidHom.monoidHomClass.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))))) f) (SetLike.coe.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.instSetLikeSubgroup.{u1} G _inst_1) K))))
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Type.{u2}} [_inst_2 : Group.{u2} H] (f : MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) (K : Subgroup.{u1} G _inst_1), Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 (MonoidHom.ker.{u1, u2} G _inst_1 H (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2))) f) K) (Nat.card.{u2} (Set.Elem.{u2} H (Set.image.{u1, u2} G H (FunLike.coe.{max (succ u1) (succ u2), succ u1, succ u2} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) G (fun (_x : G) => (fun (x._@.Mathlib.Algebra.Hom.Group._hyg.2372 : G) => H) _x) (MulHomClass.toFunLike.{max u1 u2, u1, u2} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) G H (MulOneClass.toMul.{u1} G (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) (MulOneClass.toMul.{u2} H (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) (MonoidHomClass.toMulHomClass.{max u1 u2, u1, u2} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))) G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2))) (MonoidHom.monoidHomClass.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_2)))))) f) (SetLike.coe.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.instSetLikeSubgroup.{u1} G _inst_1) K))))
 Case conversion may be inaccurate. Consider using '#align subgroup.relindex_ker Subgroup.relindex_kerₓ'. -/
 @[to_additive]
 theorem relindex_ker {H} [Group H] (f : G →* H) (K : Subgroup G) :
@@ -483,7 +483,7 @@ theorem card_mul_index : Nat.card H * H.index = Nat.card G :=
 lean 3 declaration is
   forall {G : Type.{u1}} {H : Type.{u2}} [_inst_2 : Group.{u1} G] [_inst_3 : Group.{u2} H] (f : MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_2))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_3)))), (Function.Injective.{succ u1, succ u2} G H (coeFn.{max (succ u2) (succ u1), max (succ u1) (succ u2)} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_2))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_3)))) (fun (_x : MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_2))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_3)))) => G -> H) (MonoidHom.hasCoeToFun.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_2))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_3)))) f)) -> (Dvd.Dvd.{0} Nat Nat.hasDvd (Nat.card.{u1} G) (Nat.card.{u2} H))
 but is expected to have type
-  forall {G : Type.{u2}} {H : Type.{u1}} [_inst_2 : Group.{u2} G] [_inst_3 : Group.{u1} H] (f : MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))), (Function.Injective.{succ u2, succ u1} G H (FunLike.coe.{max (succ u2) (succ u1), succ u2, succ u1} (MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) G (fun (_x : G) => (fun (x._@.Mathlib.Algebra.Hom.Group._hyg.2398 : G) => H) _x) (MulHomClass.toFunLike.{max u2 u1, u2, u1} (MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) G H (MulOneClass.toMul.{u2} G (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2)))) (MulOneClass.toMul.{u1} H (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) (MonoidHomClass.toMulHomClass.{max u2 u1, u2, u1} (MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3))) (MonoidHom.monoidHomClass.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))))) f)) -> (Dvd.dvd.{0} Nat Nat.instDvdNat (Nat.card.{u2} G) (Nat.card.{u1} H))
+  forall {G : Type.{u2}} {H : Type.{u1}} [_inst_2 : Group.{u2} G] [_inst_3 : Group.{u1} H] (f : MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))), (Function.Injective.{succ u2, succ u1} G H (FunLike.coe.{max (succ u2) (succ u1), succ u2, succ u1} (MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) G (fun (_x : G) => (fun (x._@.Mathlib.Algebra.Hom.Group._hyg.2372 : G) => H) _x) (MulHomClass.toFunLike.{max u2 u1, u2, u1} (MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) G H (MulOneClass.toMul.{u2} G (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2)))) (MulOneClass.toMul.{u1} H (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) (MonoidHomClass.toMulHomClass.{max u2 u1, u2, u1} (MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3))) (MonoidHom.monoidHomClass.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))))) f)) -> (Dvd.dvd.{0} Nat Nat.instDvdNat (Nat.card.{u2} G) (Nat.card.{u1} H))
 Case conversion may be inaccurate. Consider using '#align subgroup.nat_card_dvd_of_injective Subgroup.nat_card_dvd_of_injectiveₓ'. -/
 @[to_additive]
 theorem nat_card_dvd_of_injective {G H : Type _} [Group G] [Group H] (f : G →* H)
@@ -510,7 +510,7 @@ theorem nat_card_dvd_of_le (hHK : H ≤ K) : Nat.card H ∣ Nat.card K :=
 lean 3 declaration is
   forall {G : Type.{u1}} {H : Type.{u2}} [_inst_2 : Group.{u1} G] [_inst_3 : Group.{u2} H] (f : MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_2))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_3)))), (Function.Surjective.{succ u1, succ u2} G H (coeFn.{max (succ u2) (succ u1), max (succ u1) (succ u2)} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_2))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_3)))) (fun (_x : MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_2))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_3)))) => G -> H) (MonoidHom.hasCoeToFun.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_2))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_3)))) f)) -> (Dvd.Dvd.{0} Nat Nat.hasDvd (Nat.card.{u2} H) (Nat.card.{u1} G))
 but is expected to have type
-  forall {G : Type.{u2}} {H : Type.{u1}} [_inst_2 : Group.{u2} G] [_inst_3 : Group.{u1} H] (f : MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))), (Function.Surjective.{succ u2, succ u1} G H (FunLike.coe.{max (succ u2) (succ u1), succ u2, succ u1} (MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) G (fun (_x : G) => (fun (x._@.Mathlib.Algebra.Hom.Group._hyg.2398 : G) => H) _x) (MulHomClass.toFunLike.{max u2 u1, u2, u1} (MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) G H (MulOneClass.toMul.{u2} G (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2)))) (MulOneClass.toMul.{u1} H (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) (MonoidHomClass.toMulHomClass.{max u2 u1, u2, u1} (MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3))) (MonoidHom.monoidHomClass.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))))) f)) -> (Dvd.dvd.{0} Nat Nat.instDvdNat (Nat.card.{u1} H) (Nat.card.{u2} G))
+  forall {G : Type.{u2}} {H : Type.{u1}} [_inst_2 : Group.{u2} G] [_inst_3 : Group.{u1} H] (f : MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))), (Function.Surjective.{succ u2, succ u1} G H (FunLike.coe.{max (succ u2) (succ u1), succ u2, succ u1} (MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) G (fun (_x : G) => (fun (x._@.Mathlib.Algebra.Hom.Group._hyg.2372 : G) => H) _x) (MulHomClass.toFunLike.{max u2 u1, u2, u1} (MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) G H (MulOneClass.toMul.{u2} G (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2)))) (MulOneClass.toMul.{u1} H (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) (MonoidHomClass.toMulHomClass.{max u2 u1, u2, u1} (MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3))) (MonoidHom.monoidHomClass.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))))) f)) -> (Dvd.dvd.{0} Nat Nat.instDvdNat (Nat.card.{u1} H) (Nat.card.{u2} G))
 Case conversion may be inaccurate. Consider using '#align subgroup.nat_card_dvd_of_surjective Subgroup.nat_card_dvd_of_surjectiveₓ'. -/
 @[to_additive]
 theorem nat_card_dvd_of_surjective {G H : Type _} [Group G] [Group H] (f : G →* H)
@@ -525,7 +525,7 @@ theorem nat_card_dvd_of_surjective {G H : Type _} [Group G] [Group H] (f : G →
 lean 3 declaration is
   forall {G : Type.{u1}} {H : Type.{u2}} [_inst_2 : Group.{u1} G] [_inst_3 : Group.{u2} H] [_inst_4 : Fintype.{u1} G] [_inst_5 : Fintype.{u2} H] (f : MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_2))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_3)))), (Function.Surjective.{succ u1, succ u2} G H (coeFn.{max (succ u2) (succ u1), max (succ u1) (succ u2)} (MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_2))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_3)))) (fun (_x : MonoidHom.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_2))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_3)))) => G -> H) (MonoidHom.hasCoeToFun.{u1, u2} G H (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_2))) (Monoid.toMulOneClass.{u2} H (DivInvMonoid.toMonoid.{u2} H (Group.toDivInvMonoid.{u2} H _inst_3)))) f)) -> (Dvd.Dvd.{0} Nat Nat.hasDvd (Fintype.card.{u2} H _inst_5) (Fintype.card.{u1} G _inst_4))
 but is expected to have type
-  forall {G : Type.{u2}} {H : Type.{u1}} [_inst_2 : Group.{u2} G] [_inst_3 : Group.{u1} H] [_inst_4 : Fintype.{u2} G] [_inst_5 : Fintype.{u1} H] (f : MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))), (Function.Surjective.{succ u2, succ u1} G H (FunLike.coe.{max (succ u2) (succ u1), succ u2, succ u1} (MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) G (fun (_x : G) => (fun (x._@.Mathlib.Algebra.Hom.Group._hyg.2398 : G) => H) _x) (MulHomClass.toFunLike.{max u2 u1, u2, u1} (MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) G H (MulOneClass.toMul.{u2} G (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2)))) (MulOneClass.toMul.{u1} H (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) (MonoidHomClass.toMulHomClass.{max u2 u1, u2, u1} (MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3))) (MonoidHom.monoidHomClass.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))))) f)) -> (Dvd.dvd.{0} Nat Nat.instDvdNat (Fintype.card.{u1} H _inst_5) (Fintype.card.{u2} G _inst_4))
+  forall {G : Type.{u2}} {H : Type.{u1}} [_inst_2 : Group.{u2} G] [_inst_3 : Group.{u1} H] [_inst_4 : Fintype.{u2} G] [_inst_5 : Fintype.{u1} H] (f : MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))), (Function.Surjective.{succ u2, succ u1} G H (FunLike.coe.{max (succ u2) (succ u1), succ u2, succ u1} (MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) G (fun (_x : G) => (fun (x._@.Mathlib.Algebra.Hom.Group._hyg.2372 : G) => H) _x) (MulHomClass.toFunLike.{max u2 u1, u2, u1} (MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) G H (MulOneClass.toMul.{u2} G (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2)))) (MulOneClass.toMul.{u1} H (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) (MonoidHomClass.toMulHomClass.{max u2 u1, u2, u1} (MonoidHom.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))) G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3))) (MonoidHom.monoidHomClass.{u2, u1} G H (Monoid.toMulOneClass.{u2} G (DivInvMonoid.toMonoid.{u2} G (Group.toDivInvMonoid.{u2} G _inst_2))) (Monoid.toMulOneClass.{u1} H (DivInvMonoid.toMonoid.{u1} H (Group.toDivInvMonoid.{u1} H _inst_3)))))) f)) -> (Dvd.dvd.{0} Nat Nat.instDvdNat (Fintype.card.{u1} H _inst_5) (Fintype.card.{u2} G _inst_4))
 Case conversion may be inaccurate. Consider using '#align subgroup.card_dvd_of_surjective Subgroup.card_dvd_of_surjectiveₓ'. -/
 @[to_additive]
 theorem card_dvd_of_surjective {G H : Type _} [Group G] [Group H] [Fintype G] [Fintype H]
@@ -551,7 +551,7 @@ theorem index_map {G' : Type _} [Group G'] (f : G →* G') :
 lean 3 declaration is
   forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) {G' : Type.{u2}} [_inst_2 : Group.{u2} G'] {f : MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))}, (Function.Surjective.{succ u1, succ u2} G G' (coeFn.{max (succ u2) (succ u1), max (succ u1) (succ u2)} (MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) (fun (_x : MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) => G -> G') (MonoidHom.hasCoeToFun.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) f)) -> (Dvd.Dvd.{0} Nat Nat.hasDvd (Subgroup.index.{u2} G' _inst_2 (Subgroup.map.{u1, u2} G _inst_1 G' _inst_2 f H)) (Subgroup.index.{u1} G _inst_1 H))
 but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) {G' : Type.{u2}} [_inst_2 : Group.{u2} G'] {f : MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))}, (Function.Surjective.{succ u1, succ u2} G G' (FunLike.coe.{max (succ u1) (succ u2), succ u1, succ u2} (MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) G (fun (_x : G) => (fun (x._@.Mathlib.Algebra.Hom.Group._hyg.2398 : G) => G') _x) (MulHomClass.toFunLike.{max u1 u2, u1, u2} (MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) G G' (MulOneClass.toMul.{u1} G (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) (MulOneClass.toMul.{u2} G' (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) (MonoidHomClass.toMulHomClass.{max u1 u2, u1, u2} (MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (MonoidHom.monoidHomClass.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))))) f)) -> (Dvd.dvd.{0} Nat Nat.instDvdNat (Subgroup.index.{u2} G' _inst_2 (Subgroup.map.{u1, u2} G _inst_1 G' _inst_2 f H)) (Subgroup.index.{u1} G _inst_1 H))
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) {G' : Type.{u2}} [_inst_2 : Group.{u2} G'] {f : MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))}, (Function.Surjective.{succ u1, succ u2} G G' (FunLike.coe.{max (succ u1) (succ u2), succ u1, succ u2} (MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) G (fun (_x : G) => (fun (x._@.Mathlib.Algebra.Hom.Group._hyg.2372 : G) => G') _x) (MulHomClass.toFunLike.{max u1 u2, u1, u2} (MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) G G' (MulOneClass.toMul.{u1} G (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) (MulOneClass.toMul.{u2} G' (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) (MonoidHomClass.toMulHomClass.{max u1 u2, u1, u2} (MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (MonoidHom.monoidHomClass.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))))) f)) -> (Dvd.dvd.{0} Nat Nat.instDvdNat (Subgroup.index.{u2} G' _inst_2 (Subgroup.map.{u1, u2} G _inst_1 G' _inst_2 f H)) (Subgroup.index.{u1} G _inst_1 H))
 Case conversion may be inaccurate. Consider using '#align subgroup.index_map_dvd Subgroup.index_map_dvdₓ'. -/
 @[to_additive]
 theorem index_map_dvd {G' : Type _} [Group G'] {f : G →* G'} (hf : Function.Surjective f) :
@@ -580,7 +580,7 @@ theorem dvd_index_map {G' : Type _} [Group G'] {f : G →* G'} (hf : f.ker ≤ H
 lean 3 declaration is
   forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) {G' : Type.{u2}} [_inst_2 : Group.{u2} G'] {f : MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))}, (Function.Surjective.{succ u1, succ u2} G G' (coeFn.{max (succ u2) (succ u1), max (succ u1) (succ u2)} (MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) (fun (_x : MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) => G -> G') (MonoidHom.hasCoeToFun.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) f)) -> (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toLE.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (SetLike.partialOrder.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)))) (MonoidHom.ker.{u1, u2} G _inst_1 G' (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) f) H) -> (Eq.{1} Nat (Subgroup.index.{u2} G' _inst_2 (Subgroup.map.{u1, u2} G _inst_1 G' _inst_2 f H)) (Subgroup.index.{u1} G _inst_1 H))
 but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) {G' : Type.{u2}} [_inst_2 : Group.{u2} G'] {f : MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))}, (Function.Surjective.{succ u1, succ u2} G G' (FunLike.coe.{max (succ u1) (succ u2), succ u1, succ u2} (MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) G (fun (_x : G) => (fun (x._@.Mathlib.Algebra.Hom.Group._hyg.2398 : G) => G') _x) (MulHomClass.toFunLike.{max u1 u2, u1, u2} (MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) G G' (MulOneClass.toMul.{u1} G (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) (MulOneClass.toMul.{u2} G' (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) (MonoidHomClass.toMulHomClass.{max u1 u2, u1, u2} (MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (MonoidHom.monoidHomClass.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))))) f)) -> (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toLE.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (CompleteSemilatticeInf.toPartialOrder.{u1} (Subgroup.{u1} G _inst_1) (CompleteLattice.toCompleteSemilatticeInf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instCompleteLatticeSubgroup.{u1} G _inst_1))))) (MonoidHom.ker.{u1, u2} G _inst_1 G' (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) f) H) -> (Eq.{1} Nat (Subgroup.index.{u2} G' _inst_2 (Subgroup.map.{u1, u2} G _inst_1 G' _inst_2 f H)) (Subgroup.index.{u1} G _inst_1 H))
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) {G' : Type.{u2}} [_inst_2 : Group.{u2} G'] {f : MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))}, (Function.Surjective.{succ u1, succ u2} G G' (FunLike.coe.{max (succ u1) (succ u2), succ u1, succ u2} (MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) G (fun (_x : G) => (fun (x._@.Mathlib.Algebra.Hom.Group._hyg.2372 : G) => G') _x) (MulHomClass.toFunLike.{max u1 u2, u1, u2} (MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) G G' (MulOneClass.toMul.{u1} G (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1)))) (MulOneClass.toMul.{u2} G' (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) (MonoidHomClass.toMulHomClass.{max u1 u2, u1, u2} (MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) (MonoidHom.monoidHomClass.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))))) f)) -> (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toLE.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (CompleteSemilatticeInf.toPartialOrder.{u1} (Subgroup.{u1} G _inst_1) (CompleteLattice.toCompleteSemilatticeInf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instCompleteLatticeSubgroup.{u1} G _inst_1))))) (MonoidHom.ker.{u1, u2} G _inst_1 G' (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) f) H) -> (Eq.{1} Nat (Subgroup.index.{u2} G' _inst_2 (Subgroup.map.{u1, u2} G _inst_1 G' _inst_2 f H)) (Subgroup.index.{u1} G _inst_1 H))
 Case conversion may be inaccurate. Consider using '#align subgroup.index_map_eq Subgroup.index_map_eqₓ'. -/
 @[to_additive]
 theorem index_map_eq {G' : Type _} [Group G'] {f : G →* G'} (hf1 : Function.Surjective f)

mathlib commit https://github.com/leanprover-community/mathlib/commit/9da1b3534b65d9661eb8f42443598a92bbb49211

@@ -184,9 +184,9 @@ theorem relindex_mul_relindex (hHK : H ≤ K) (hKL : K ≤ L) :
 
 /- warning: subgroup.inf_relindex_right -> Subgroup.inf_relindex_right is a dubious translation:
 lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) (K : Subgroup.{u1} G _inst_1), Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 (HasInf.inf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.hasInf.{u1} G _inst_1) H K) K) (Subgroup.relindex.{u1} G _inst_1 H K)
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) (K : Subgroup.{u1} G _inst_1), Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 (Inf.inf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.hasInf.{u1} G _inst_1) H K) K) (Subgroup.relindex.{u1} G _inst_1 H K)
 but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) (K : Subgroup.{u1} G _inst_1), Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 (HasInf.inf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instHasInfSubgroup.{u1} G _inst_1) H K) K) (Subgroup.relindex.{u1} G _inst_1 H K)
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) (K : Subgroup.{u1} G _inst_1), Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 (Inf.inf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instInfSubgroup.{u1} G _inst_1) H K) K) (Subgroup.relindex.{u1} G _inst_1 H K)
 Case conversion may be inaccurate. Consider using '#align subgroup.inf_relindex_right Subgroup.inf_relindex_rightₓ'. -/
 @[to_additive]
 theorem inf_relindex_right : (H ⊓ K).relindex K = H.relindex K := by
@@ -196,9 +196,9 @@ theorem inf_relindex_right : (H ⊓ K).relindex K = H.relindex K := by
 
 /- warning: subgroup.inf_relindex_left -> Subgroup.inf_relindex_left is a dubious translation:
 lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) (K : Subgroup.{u1} G _inst_1), Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 (HasInf.inf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.hasInf.{u1} G _inst_1) H K) H) (Subgroup.relindex.{u1} G _inst_1 K H)
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) (K : Subgroup.{u1} G _inst_1), Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 (Inf.inf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.hasInf.{u1} G _inst_1) H K) H) (Subgroup.relindex.{u1} G _inst_1 K H)
 but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) (K : Subgroup.{u1} G _inst_1), Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 (HasInf.inf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instHasInfSubgroup.{u1} G _inst_1) H K) H) (Subgroup.relindex.{u1} G _inst_1 K H)
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) (K : Subgroup.{u1} G _inst_1), Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 (Inf.inf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instInfSubgroup.{u1} G _inst_1) H K) H) (Subgroup.relindex.{u1} G _inst_1 K H)
 Case conversion may be inaccurate. Consider using '#align subgroup.inf_relindex_left Subgroup.inf_relindex_leftₓ'. -/
 @[to_additive]
 theorem inf_relindex_left : (H ⊓ K).relindex H = K.relindex H := by
@@ -208,9 +208,9 @@ theorem inf_relindex_left : (H ⊓ K).relindex H = K.relindex H := by
 
 /- warning: subgroup.relindex_inf_mul_relindex -> Subgroup.relindex_inf_mul_relindex is a dubious translation:
 lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) (K : Subgroup.{u1} G _inst_1) (L : Subgroup.{u1} G _inst_1), Eq.{1} Nat (HMul.hMul.{0, 0, 0} Nat Nat Nat (instHMul.{0} Nat Nat.hasMul) (Subgroup.relindex.{u1} G _inst_1 H (HasInf.inf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.hasInf.{u1} G _inst_1) K L)) (Subgroup.relindex.{u1} G _inst_1 K L)) (Subgroup.relindex.{u1} G _inst_1 (HasInf.inf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.hasInf.{u1} G _inst_1) H K) L)
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) (K : Subgroup.{u1} G _inst_1) (L : Subgroup.{u1} G _inst_1), Eq.{1} Nat (HMul.hMul.{0, 0, 0} Nat Nat Nat (instHMul.{0} Nat Nat.hasMul) (Subgroup.relindex.{u1} G _inst_1 H (Inf.inf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.hasInf.{u1} G _inst_1) K L)) (Subgroup.relindex.{u1} G _inst_1 K L)) (Subgroup.relindex.{u1} G _inst_1 (Inf.inf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.hasInf.{u1} G _inst_1) H K) L)
 but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) (K : Subgroup.{u1} G _inst_1) (L : Subgroup.{u1} G _inst_1), Eq.{1} Nat (HMul.hMul.{0, 0, 0} Nat Nat Nat (instHMul.{0} Nat instMulNat) (Subgroup.relindex.{u1} G _inst_1 H (HasInf.inf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instHasInfSubgroup.{u1} G _inst_1) K L)) (Subgroup.relindex.{u1} G _inst_1 K L)) (Subgroup.relindex.{u1} G _inst_1 (HasInf.inf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instHasInfSubgroup.{u1} G _inst_1) H K) L)
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) (K : Subgroup.{u1} G _inst_1) (L : Subgroup.{u1} G _inst_1), Eq.{1} Nat (HMul.hMul.{0, 0, 0} Nat Nat Nat (instHMul.{0} Nat instMulNat) (Subgroup.relindex.{u1} G _inst_1 H (Inf.inf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instInfSubgroup.{u1} G _inst_1) K L)) (Subgroup.relindex.{u1} G _inst_1 K L)) (Subgroup.relindex.{u1} G _inst_1 (Inf.inf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instInfSubgroup.{u1} G _inst_1) H K) L)
 Case conversion may be inaccurate. Consider using '#align subgroup.relindex_inf_mul_relindex Subgroup.relindex_inf_mul_relindexₓ'. -/
 @[to_additive relindex_inf_mul_relindex]
 theorem relindex_inf_mul_relindex : H.relindex (K ⊓ L) * K.relindex L = (H ⊓ K).relindex L := by
@@ -221,9 +221,9 @@ theorem relindex_inf_mul_relindex : H.relindex (K ⊓ L) * K.relindex L = (H ⊓
 
 /- warning: subgroup.relindex_sup_right -> Subgroup.relindex_sup_right is a dubious translation:
 lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) (K : Subgroup.{u1} G _inst_1) [_inst_2 : Subgroup.Normal.{u1} G _inst_1 K], Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 K (HasSup.sup.{u1} (Subgroup.{u1} G _inst_1) (SemilatticeSup.toHasSup.{u1} (Subgroup.{u1} G _inst_1) (Lattice.toSemilatticeSup.{u1} (Subgroup.{u1} G _inst_1) (ConditionallyCompleteLattice.toLattice.{u1} (Subgroup.{u1} G _inst_1) (CompleteLattice.toConditionallyCompleteLattice.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.completeLattice.{u1} G _inst_1))))) H K)) (Subgroup.relindex.{u1} G _inst_1 K H)
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) (K : Subgroup.{u1} G _inst_1) [_inst_2 : Subgroup.Normal.{u1} G _inst_1 K], Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 K (Sup.sup.{u1} (Subgroup.{u1} G _inst_1) (SemilatticeSup.toHasSup.{u1} (Subgroup.{u1} G _inst_1) (Lattice.toSemilatticeSup.{u1} (Subgroup.{u1} G _inst_1) (ConditionallyCompleteLattice.toLattice.{u1} (Subgroup.{u1} G _inst_1) (CompleteLattice.toConditionallyCompleteLattice.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.completeLattice.{u1} G _inst_1))))) H K)) (Subgroup.relindex.{u1} G _inst_1 K H)
 but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) (K : Subgroup.{u1} G _inst_1) [_inst_2 : Subgroup.Normal.{u1} G _inst_1 K], Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 K (HasSup.sup.{u1} (Subgroup.{u1} G _inst_1) (SemilatticeSup.toHasSup.{u1} (Subgroup.{u1} G _inst_1) (Lattice.toSemilatticeSup.{u1} (Subgroup.{u1} G _inst_1) (ConditionallyCompleteLattice.toLattice.{u1} (Subgroup.{u1} G _inst_1) (CompleteLattice.toConditionallyCompleteLattice.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instCompleteLatticeSubgroup.{u1} G _inst_1))))) H K)) (Subgroup.relindex.{u1} G _inst_1 K H)
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) (K : Subgroup.{u1} G _inst_1) [_inst_2 : Subgroup.Normal.{u1} G _inst_1 K], Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 K (Sup.sup.{u1} (Subgroup.{u1} G _inst_1) (SemilatticeSup.toSup.{u1} (Subgroup.{u1} G _inst_1) (Lattice.toSemilatticeSup.{u1} (Subgroup.{u1} G _inst_1) (ConditionallyCompleteLattice.toLattice.{u1} (Subgroup.{u1} G _inst_1) (CompleteLattice.toConditionallyCompleteLattice.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instCompleteLatticeSubgroup.{u1} G _inst_1))))) H K)) (Subgroup.relindex.{u1} G _inst_1 K H)
 Case conversion may be inaccurate. Consider using '#align subgroup.relindex_sup_right Subgroup.relindex_sup_rightₓ'. -/
 @[simp, to_additive]
 theorem relindex_sup_right [K.Normal] : K.relindex (H ⊔ K) = K.relindex H :=
@@ -233,9 +233,9 @@ theorem relindex_sup_right [K.Normal] : K.relindex (H ⊔ K) = K.relindex H :=
 
 /- warning: subgroup.relindex_sup_left -> Subgroup.relindex_sup_left is a dubious translation:
 lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) (K : Subgroup.{u1} G _inst_1) [_inst_2 : Subgroup.Normal.{u1} G _inst_1 K], Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 K (HasSup.sup.{u1} (Subgroup.{u1} G _inst_1) (SemilatticeSup.toHasSup.{u1} (Subgroup.{u1} G _inst_1) (Lattice.toSemilatticeSup.{u1} (Subgroup.{u1} G _inst_1) (ConditionallyCompleteLattice.toLattice.{u1} (Subgroup.{u1} G _inst_1) (CompleteLattice.toConditionallyCompleteLattice.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.completeLattice.{u1} G _inst_1))))) K H)) (Subgroup.relindex.{u1} G _inst_1 K H)
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) (K : Subgroup.{u1} G _inst_1) [_inst_2 : Subgroup.Normal.{u1} G _inst_1 K], Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 K (Sup.sup.{u1} (Subgroup.{u1} G _inst_1) (SemilatticeSup.toHasSup.{u1} (Subgroup.{u1} G _inst_1) (Lattice.toSemilatticeSup.{u1} (Subgroup.{u1} G _inst_1) (ConditionallyCompleteLattice.toLattice.{u1} (Subgroup.{u1} G _inst_1) (CompleteLattice.toConditionallyCompleteLattice.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.completeLattice.{u1} G _inst_1))))) K H)) (Subgroup.relindex.{u1} G _inst_1 K H)
 but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) (K : Subgroup.{u1} G _inst_1) [_inst_2 : Subgroup.Normal.{u1} G _inst_1 K], Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 K (HasSup.sup.{u1} (Subgroup.{u1} G _inst_1) (SemilatticeSup.toHasSup.{u1} (Subgroup.{u1} G _inst_1) (Lattice.toSemilatticeSup.{u1} (Subgroup.{u1} G _inst_1) (ConditionallyCompleteLattice.toLattice.{u1} (Subgroup.{u1} G _inst_1) (CompleteLattice.toConditionallyCompleteLattice.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instCompleteLatticeSubgroup.{u1} G _inst_1))))) K H)) (Subgroup.relindex.{u1} G _inst_1 K H)
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) (K : Subgroup.{u1} G _inst_1) [_inst_2 : Subgroup.Normal.{u1} G _inst_1 K], Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 K (Sup.sup.{u1} (Subgroup.{u1} G _inst_1) (SemilatticeSup.toSup.{u1} (Subgroup.{u1} G _inst_1) (Lattice.toSemilatticeSup.{u1} (Subgroup.{u1} G _inst_1) (ConditionallyCompleteLattice.toLattice.{u1} (Subgroup.{u1} G _inst_1) (CompleteLattice.toConditionallyCompleteLattice.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instCompleteLatticeSubgroup.{u1} G _inst_1))))) K H)) (Subgroup.relindex.{u1} G _inst_1 K H)
 Case conversion may be inaccurate. Consider using '#align subgroup.relindex_sup_left Subgroup.relindex_sup_leftₓ'. -/
 @[simp, to_additive]
 theorem relindex_sup_left [K.Normal] : K.relindex (K ⊔ H) = K.relindex H := by
@@ -536,9 +536,9 @@ theorem card_dvd_of_surjective {G H : Type _} [Group G] [Group H] [Fintype G] [F
 
 /- warning: subgroup.index_map -> Subgroup.index_map is a dubious translation:
 lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) {G' : Type.{u2}} [_inst_2 : Group.{u2} G'] (f : MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))), Eq.{1} Nat (Subgroup.index.{u2} G' _inst_2 (Subgroup.map.{u1, u2} G _inst_1 G' _inst_2 f H)) (HMul.hMul.{0, 0, 0} Nat Nat Nat (instHMul.{0} Nat Nat.hasMul) (Subgroup.index.{u1} G _inst_1 (HasSup.sup.{u1} (Subgroup.{u1} G _inst_1) (SemilatticeSup.toHasSup.{u1} (Subgroup.{u1} G _inst_1) (Lattice.toSemilatticeSup.{u1} (Subgroup.{u1} G _inst_1) (ConditionallyCompleteLattice.toLattice.{u1} (Subgroup.{u1} G _inst_1) (CompleteLattice.toConditionallyCompleteLattice.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.completeLattice.{u1} G _inst_1))))) H (MonoidHom.ker.{u1, u2} G _inst_1 G' (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) f))) (Subgroup.index.{u2} G' _inst_2 (MonoidHom.range.{u1, u2} G _inst_1 G' _inst_2 f)))
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) {G' : Type.{u2}} [_inst_2 : Group.{u2} G'] (f : MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))), Eq.{1} Nat (Subgroup.index.{u2} G' _inst_2 (Subgroup.map.{u1, u2} G _inst_1 G' _inst_2 f H)) (HMul.hMul.{0, 0, 0} Nat Nat Nat (instHMul.{0} Nat Nat.hasMul) (Subgroup.index.{u1} G _inst_1 (Sup.sup.{u1} (Subgroup.{u1} G _inst_1) (SemilatticeSup.toHasSup.{u1} (Subgroup.{u1} G _inst_1) (Lattice.toSemilatticeSup.{u1} (Subgroup.{u1} G _inst_1) (ConditionallyCompleteLattice.toLattice.{u1} (Subgroup.{u1} G _inst_1) (CompleteLattice.toConditionallyCompleteLattice.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.completeLattice.{u1} G _inst_1))))) H (MonoidHom.ker.{u1, u2} G _inst_1 G' (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) f))) (Subgroup.index.{u2} G' _inst_2 (MonoidHom.range.{u1, u2} G _inst_1 G' _inst_2 f)))
 but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) {G' : Type.{u2}} [_inst_2 : Group.{u2} G'] (f : MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))), Eq.{1} Nat (Subgroup.index.{u2} G' _inst_2 (Subgroup.map.{u1, u2} G _inst_1 G' _inst_2 f H)) (HMul.hMul.{0, 0, 0} Nat Nat Nat (instHMul.{0} Nat instMulNat) (Subgroup.index.{u1} G _inst_1 (HasSup.sup.{u1} (Subgroup.{u1} G _inst_1) (SemilatticeSup.toHasSup.{u1} (Subgroup.{u1} G _inst_1) (Lattice.toSemilatticeSup.{u1} (Subgroup.{u1} G _inst_1) (ConditionallyCompleteLattice.toLattice.{u1} (Subgroup.{u1} G _inst_1) (CompleteLattice.toConditionallyCompleteLattice.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instCompleteLatticeSubgroup.{u1} G _inst_1))))) H (MonoidHom.ker.{u1, u2} G _inst_1 G' (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) f))) (Subgroup.index.{u2} G' _inst_2 (MonoidHom.range.{u1, u2} G _inst_1 G' _inst_2 f)))
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] (H : Subgroup.{u1} G _inst_1) {G' : Type.{u2}} [_inst_2 : Group.{u2} G'] (f : MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))), Eq.{1} Nat (Subgroup.index.{u2} G' _inst_2 (Subgroup.map.{u1, u2} G _inst_1 G' _inst_2 f H)) (HMul.hMul.{0, 0, 0} Nat Nat Nat (instHMul.{0} Nat instMulNat) (Subgroup.index.{u1} G _inst_1 (Sup.sup.{u1} (Subgroup.{u1} G _inst_1) (SemilatticeSup.toSup.{u1} (Subgroup.{u1} G _inst_1) (Lattice.toSemilatticeSup.{u1} (Subgroup.{u1} G _inst_1) (ConditionallyCompleteLattice.toLattice.{u1} (Subgroup.{u1} G _inst_1) (CompleteLattice.toConditionallyCompleteLattice.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instCompleteLatticeSubgroup.{u1} G _inst_1))))) H (MonoidHom.ker.{u1, u2} G _inst_1 G' (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) f))) (Subgroup.index.{u2} G' _inst_2 (MonoidHom.range.{u1, u2} G _inst_1 G' _inst_2 f)))
 Case conversion may be inaccurate. Consider using '#align subgroup.index_map Subgroup.index_mapₓ'. -/
 @[to_additive]
 theorem index_map {G' : Type _} [Group G'] (f : G →* G') :
@@ -691,9 +691,9 @@ theorem relindex_ne_zero_trans (hHK : H.relindex K ≠ 0) (hKL : K.relindex L 
 
 /- warning: subgroup.relindex_inf_ne_zero -> Subgroup.relindex_inf_ne_zero is a dubious translation:
 lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1} {L : Subgroup.{u1} G _inst_1}, (Ne.{1} Nat (Subgroup.relindex.{u1} G _inst_1 H L) (OfNat.ofNat.{0} Nat 0 (OfNat.mk.{0} Nat 0 (Zero.zero.{0} Nat Nat.hasZero)))) -> (Ne.{1} Nat (Subgroup.relindex.{u1} G _inst_1 K L) (OfNat.ofNat.{0} Nat 0 (OfNat.mk.{0} Nat 0 (Zero.zero.{0} Nat Nat.hasZero)))) -> (Ne.{1} Nat (Subgroup.relindex.{u1} G _inst_1 (HasInf.inf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.hasInf.{u1} G _inst_1) H K) L) (OfNat.ofNat.{0} Nat 0 (OfNat.mk.{0} Nat 0 (Zero.zero.{0} Nat Nat.hasZero))))
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1} {L : Subgroup.{u1} G _inst_1}, (Ne.{1} Nat (Subgroup.relindex.{u1} G _inst_1 H L) (OfNat.ofNat.{0} Nat 0 (OfNat.mk.{0} Nat 0 (Zero.zero.{0} Nat Nat.hasZero)))) -> (Ne.{1} Nat (Subgroup.relindex.{u1} G _inst_1 K L) (OfNat.ofNat.{0} Nat 0 (OfNat.mk.{0} Nat 0 (Zero.zero.{0} Nat Nat.hasZero)))) -> (Ne.{1} Nat (Subgroup.relindex.{u1} G _inst_1 (Inf.inf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.hasInf.{u1} G _inst_1) H K) L) (OfNat.ofNat.{0} Nat 0 (OfNat.mk.{0} Nat 0 (Zero.zero.{0} Nat Nat.hasZero))))
 but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1} {L : Subgroup.{u1} G _inst_1}, (Ne.{1} Nat (Subgroup.relindex.{u1} G _inst_1 H L) (OfNat.ofNat.{0} Nat 0 (instOfNatNat 0))) -> (Ne.{1} Nat (Subgroup.relindex.{u1} G _inst_1 K L) (OfNat.ofNat.{0} Nat 0 (instOfNatNat 0))) -> (Ne.{1} Nat (Subgroup.relindex.{u1} G _inst_1 (HasInf.inf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instHasInfSubgroup.{u1} G _inst_1) H K) L) (OfNat.ofNat.{0} Nat 0 (instOfNatNat 0)))
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1} {L : Subgroup.{u1} G _inst_1}, (Ne.{1} Nat (Subgroup.relindex.{u1} G _inst_1 H L) (OfNat.ofNat.{0} Nat 0 (instOfNatNat 0))) -> (Ne.{1} Nat (Subgroup.relindex.{u1} G _inst_1 K L) (OfNat.ofNat.{0} Nat 0 (instOfNatNat 0))) -> (Ne.{1} Nat (Subgroup.relindex.{u1} G _inst_1 (Inf.inf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instInfSubgroup.{u1} G _inst_1) H K) L) (OfNat.ofNat.{0} Nat 0 (instOfNatNat 0)))
 Case conversion may be inaccurate. Consider using '#align subgroup.relindex_inf_ne_zero Subgroup.relindex_inf_ne_zeroₓ'. -/
 @[to_additive]
 theorem relindex_inf_ne_zero (hH : H.relindex L ≠ 0) (hK : K.relindex L ≠ 0) :
@@ -708,9 +708,9 @@ theorem relindex_inf_ne_zero (hH : H.relindex L ≠ 0) (hK : K.relindex L ≠ 0)
 
 /- warning: subgroup.index_inf_ne_zero -> Subgroup.index_inf_ne_zero is a dubious translation:
 lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1}, (Ne.{1} Nat (Subgroup.index.{u1} G _inst_1 H) (OfNat.ofNat.{0} Nat 0 (OfNat.mk.{0} Nat 0 (Zero.zero.{0} Nat Nat.hasZero)))) -> (Ne.{1} Nat (Subgroup.index.{u1} G _inst_1 K) (OfNat.ofNat.{0} Nat 0 (OfNat.mk.{0} Nat 0 (Zero.zero.{0} Nat Nat.hasZero)))) -> (Ne.{1} Nat (Subgroup.index.{u1} G _inst_1 (HasInf.inf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.hasInf.{u1} G _inst_1) H K)) (OfNat.ofNat.{0} Nat 0 (OfNat.mk.{0} Nat 0 (Zero.zero.{0} Nat Nat.hasZero))))
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1}, (Ne.{1} Nat (Subgroup.index.{u1} G _inst_1 H) (OfNat.ofNat.{0} Nat 0 (OfNat.mk.{0} Nat 0 (Zero.zero.{0} Nat Nat.hasZero)))) -> (Ne.{1} Nat (Subgroup.index.{u1} G _inst_1 K) (OfNat.ofNat.{0} Nat 0 (OfNat.mk.{0} Nat 0 (Zero.zero.{0} Nat Nat.hasZero)))) -> (Ne.{1} Nat (Subgroup.index.{u1} G _inst_1 (Inf.inf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.hasInf.{u1} G _inst_1) H K)) (OfNat.ofNat.{0} Nat 0 (OfNat.mk.{0} Nat 0 (Zero.zero.{0} Nat Nat.hasZero))))
 but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1}, (Ne.{1} Nat (Subgroup.index.{u1} G _inst_1 H) (OfNat.ofNat.{0} Nat 0 (instOfNatNat 0))) -> (Ne.{1} Nat (Subgroup.index.{u1} G _inst_1 K) (OfNat.ofNat.{0} Nat 0 (instOfNatNat 0))) -> (Ne.{1} Nat (Subgroup.index.{u1} G _inst_1 (HasInf.inf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instHasInfSubgroup.{u1} G _inst_1) H K)) (OfNat.ofNat.{0} Nat 0 (instOfNatNat 0)))
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1}, (Ne.{1} Nat (Subgroup.index.{u1} G _inst_1 H) (OfNat.ofNat.{0} Nat 0 (instOfNatNat 0))) -> (Ne.{1} Nat (Subgroup.index.{u1} G _inst_1 K) (OfNat.ofNat.{0} Nat 0 (instOfNatNat 0))) -> (Ne.{1} Nat (Subgroup.index.{u1} G _inst_1 (Inf.inf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instInfSubgroup.{u1} G _inst_1) H K)) (OfNat.ofNat.{0} Nat 0 (instOfNatNat 0)))
 Case conversion may be inaccurate. Consider using '#align subgroup.index_inf_ne_zero Subgroup.index_inf_ne_zeroₓ'. -/
 @[to_additive]
 theorem index_inf_ne_zero (hH : H.index ≠ 0) (hK : K.index ≠ 0) : (H ⊓ K).index ≠ 0 :=
@@ -722,9 +722,9 @@ theorem index_inf_ne_zero (hH : H.index ≠ 0) (hK : K.index ≠ 0) : (H ⊓ K).
 
 /- warning: subgroup.relindex_inf_le -> Subgroup.relindex_inf_le is a dubious translation:
 lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1} {L : Subgroup.{u1} G _inst_1}, LE.le.{0} Nat Nat.hasLe (Subgroup.relindex.{u1} G _inst_1 (HasInf.inf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.hasInf.{u1} G _inst_1) H K) L) (HMul.hMul.{0, 0, 0} Nat Nat Nat (instHMul.{0} Nat Nat.hasMul) (Subgroup.relindex.{u1} G _inst_1 H L) (Subgroup.relindex.{u1} G _inst_1 K L))
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1} {L : Subgroup.{u1} G _inst_1}, LE.le.{0} Nat Nat.hasLe (Subgroup.relindex.{u1} G _inst_1 (Inf.inf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.hasInf.{u1} G _inst_1) H K) L) (HMul.hMul.{0, 0, 0} Nat Nat Nat (instHMul.{0} Nat Nat.hasMul) (Subgroup.relindex.{u1} G _inst_1 H L) (Subgroup.relindex.{u1} G _inst_1 K L))
 but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1} {L : Subgroup.{u1} G _inst_1}, LE.le.{0} Nat instLENat (Subgroup.relindex.{u1} G _inst_1 (HasInf.inf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instHasInfSubgroup.{u1} G _inst_1) H K) L) (HMul.hMul.{0, 0, 0} Nat Nat Nat (instHMul.{0} Nat instMulNat) (Subgroup.relindex.{u1} G _inst_1 H L) (Subgroup.relindex.{u1} G _inst_1 K L))
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1} {L : Subgroup.{u1} G _inst_1}, LE.le.{0} Nat instLENat (Subgroup.relindex.{u1} G _inst_1 (Inf.inf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instInfSubgroup.{u1} G _inst_1) H K) L) (HMul.hMul.{0, 0, 0} Nat Nat Nat (instHMul.{0} Nat instMulNat) (Subgroup.relindex.{u1} G _inst_1 H L) (Subgroup.relindex.{u1} G _inst_1 K L))
 Case conversion may be inaccurate. Consider using '#align subgroup.relindex_inf_le Subgroup.relindex_inf_leₓ'. -/
 @[to_additive]
 theorem relindex_inf_le : (H ⊓ K).relindex L ≤ H.relindex L * K.relindex L :=
@@ -739,9 +739,9 @@ theorem relindex_inf_le : (H ⊓ K).relindex L ≤ H.relindex L * K.relindex L :
 
 /- warning: subgroup.index_inf_le -> Subgroup.index_inf_le is a dubious translation:
 lean 3 declaration is
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1}, LE.le.{0} Nat Nat.hasLe (Subgroup.index.{u1} G _inst_1 (HasInf.inf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.hasInf.{u1} G _inst_1) H K)) (HMul.hMul.{0, 0, 0} Nat Nat Nat (instHMul.{0} Nat Nat.hasMul) (Subgroup.index.{u1} G _inst_1 H) (Subgroup.index.{u1} G _inst_1 K))
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1}, LE.le.{0} Nat Nat.hasLe (Subgroup.index.{u1} G _inst_1 (Inf.inf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.hasInf.{u1} G _inst_1) H K)) (HMul.hMul.{0, 0, 0} Nat Nat Nat (instHMul.{0} Nat Nat.hasMul) (Subgroup.index.{u1} G _inst_1 H) (Subgroup.index.{u1} G _inst_1 K))
 but is expected to have type
-  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1}, LE.le.{0} Nat instLENat (Subgroup.index.{u1} G _inst_1 (HasInf.inf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instHasInfSubgroup.{u1} G _inst_1) H K)) (HMul.hMul.{0, 0, 0} Nat Nat Nat (instHMul.{0} Nat instMulNat) (Subgroup.index.{u1} G _inst_1 H) (Subgroup.index.{u1} G _inst_1 K))
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1}, LE.le.{0} Nat instLENat (Subgroup.index.{u1} G _inst_1 (Inf.inf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instInfSubgroup.{u1} G _inst_1) H K)) (HMul.hMul.{0, 0, 0} Nat Nat Nat (instHMul.{0} Nat instMulNat) (Subgroup.index.{u1} G _inst_1 H) (Subgroup.index.{u1} G _inst_1 K))
 Case conversion may be inaccurate. Consider using '#align subgroup.index_inf_le Subgroup.index_inf_leₓ'. -/
 @[to_additive]
 theorem index_inf_le : (H ⊓ K).index ≤ H.index * K.index := by

mathlib commit https://github.com/leanprover-community/mathlib/commit/22131150f88a2d125713ffa0f4693e3355b1eb49

@@ -706,7 +706,12 @@ theorem relindex_inf_ne_zero (hH : H.relindex L ≠ 0) (hK : K.relindex L ≠ 0)
 #align subgroup.relindex_inf_ne_zero Subgroup.relindex_inf_ne_zero
 #align add_subgroup.relindex_inf_ne_zero AddSubgroup.relindex_inf_ne_zero
 
-#print Subgroup.index_inf_ne_zero /-
+/- warning: subgroup.index_inf_ne_zero -> Subgroup.index_inf_ne_zero is a dubious translation:
+lean 3 declaration is
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1}, (Ne.{1} Nat (Subgroup.index.{u1} G _inst_1 H) (OfNat.ofNat.{0} Nat 0 (OfNat.mk.{0} Nat 0 (Zero.zero.{0} Nat Nat.hasZero)))) -> (Ne.{1} Nat (Subgroup.index.{u1} G _inst_1 K) (OfNat.ofNat.{0} Nat 0 (OfNat.mk.{0} Nat 0 (Zero.zero.{0} Nat Nat.hasZero)))) -> (Ne.{1} Nat (Subgroup.index.{u1} G _inst_1 (HasInf.inf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.hasInf.{u1} G _inst_1) H K)) (OfNat.ofNat.{0} Nat 0 (OfNat.mk.{0} Nat 0 (Zero.zero.{0} Nat Nat.hasZero))))
+but is expected to have type
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1}, (Ne.{1} Nat (Subgroup.index.{u1} G _inst_1 H) (OfNat.ofNat.{0} Nat 0 (instOfNatNat 0))) -> (Ne.{1} Nat (Subgroup.index.{u1} G _inst_1 K) (OfNat.ofNat.{0} Nat 0 (instOfNatNat 0))) -> (Ne.{1} Nat (Subgroup.index.{u1} G _inst_1 (HasInf.inf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instHasInfSubgroup.{u1} G _inst_1) H K)) (OfNat.ofNat.{0} Nat 0 (instOfNatNat 0)))
+Case conversion may be inaccurate. Consider using '#align subgroup.index_inf_ne_zero Subgroup.index_inf_ne_zeroₓ'. -/
 @[to_additive]
 theorem index_inf_ne_zero (hH : H.index ≠ 0) (hK : K.index ≠ 0) : (H ⊓ K).index ≠ 0 :=
   by
@@ -714,9 +719,13 @@ theorem index_inf_ne_zero (hH : H.index ≠ 0) (hK : K.index ≠ 0) : (H ⊓ K).
   exact relindex_inf_ne_zero hH hK
 #align subgroup.index_inf_ne_zero Subgroup.index_inf_ne_zero
 #align add_subgroup.index_inf_ne_zero AddSubgroup.index_inf_ne_zero
--/
 
-#print Subgroup.relindex_inf_le /-
+/- warning: subgroup.relindex_inf_le -> Subgroup.relindex_inf_le is a dubious translation:
+lean 3 declaration is
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1} {L : Subgroup.{u1} G _inst_1}, LE.le.{0} Nat Nat.hasLe (Subgroup.relindex.{u1} G _inst_1 (HasInf.inf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.hasInf.{u1} G _inst_1) H K) L) (HMul.hMul.{0, 0, 0} Nat Nat Nat (instHMul.{0} Nat Nat.hasMul) (Subgroup.relindex.{u1} G _inst_1 H L) (Subgroup.relindex.{u1} G _inst_1 K L))
+but is expected to have type
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1} {L : Subgroup.{u1} G _inst_1}, LE.le.{0} Nat instLENat (Subgroup.relindex.{u1} G _inst_1 (HasInf.inf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instHasInfSubgroup.{u1} G _inst_1) H K) L) (HMul.hMul.{0, 0, 0} Nat Nat Nat (instHMul.{0} Nat instMulNat) (Subgroup.relindex.{u1} G _inst_1 H L) (Subgroup.relindex.{u1} G _inst_1 K L))
+Case conversion may be inaccurate. Consider using '#align subgroup.relindex_inf_le Subgroup.relindex_inf_leₓ'. -/
 @[to_additive]
 theorem relindex_inf_le : (H ⊓ K).relindex L ≤ H.relindex L * K.relindex L :=
   by
@@ -727,15 +736,18 @@ theorem relindex_inf_le : (H ⊓ K).relindex L ≤ H.relindex L * K.relindex L :
   exact mul_le_mul_right' (relindex_le_of_le_right inf_le_right h) (K.relindex L)
 #align subgroup.relindex_inf_le Subgroup.relindex_inf_le
 #align add_subgroup.relindex_inf_le AddSubgroup.relindex_inf_le
--/
 
-#print Subgroup.index_inf_le /-
+/- warning: subgroup.index_inf_le -> Subgroup.index_inf_le is a dubious translation:
+lean 3 declaration is
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1}, LE.le.{0} Nat Nat.hasLe (Subgroup.index.{u1} G _inst_1 (HasInf.inf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.hasInf.{u1} G _inst_1) H K)) (HMul.hMul.{0, 0, 0} Nat Nat Nat (instHMul.{0} Nat Nat.hasMul) (Subgroup.index.{u1} G _inst_1 H) (Subgroup.index.{u1} G _inst_1 K))
+but is expected to have type
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1}, LE.le.{0} Nat instLENat (Subgroup.index.{u1} G _inst_1 (HasInf.inf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instHasInfSubgroup.{u1} G _inst_1) H K)) (HMul.hMul.{0, 0, 0} Nat Nat Nat (instHMul.{0} Nat instMulNat) (Subgroup.index.{u1} G _inst_1 H) (Subgroup.index.{u1} G _inst_1 K))
+Case conversion may be inaccurate. Consider using '#align subgroup.index_inf_le Subgroup.index_inf_leₓ'. -/
 @[to_additive]
 theorem index_inf_le : (H ⊓ K).index ≤ H.index * K.index := by
   simp_rw [← relindex_top_right, relindex_inf_le]
 #align subgroup.index_inf_le Subgroup.index_inf_le
 #align add_subgroup.index_inf_le AddSubgroup.index_inf_le
--/
 
 #print Subgroup.relindex_infᵢ_ne_zero /-
 @[to_additive]
@@ -781,7 +793,12 @@ theorem index_infᵢ_le {ι : Type _} [Fintype ι] (f : ι → Subgroup G) :
 #align add_subgroup.index_infi_le AddSubgroup.index_infᵢ_le
 -/
 
-#print Subgroup.index_eq_one /-
+/- warning: subgroup.index_eq_one -> Subgroup.index_eq_one is a dubious translation:
+lean 3 declaration is
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1}, Iff (Eq.{1} Nat (Subgroup.index.{u1} G _inst_1 H) (OfNat.ofNat.{0} Nat 1 (OfNat.mk.{0} Nat 1 (One.one.{0} Nat Nat.hasOne)))) (Eq.{succ u1} (Subgroup.{u1} G _inst_1) H (Top.top.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.hasTop.{u1} G _inst_1)))
+but is expected to have type
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1}, Iff (Eq.{1} Nat (Subgroup.index.{u1} G _inst_1 H) (OfNat.ofNat.{0} Nat 1 (instOfNatNat 1))) (Eq.{succ u1} (Subgroup.{u1} G _inst_1) H (Top.top.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instTopSubgroup.{u1} G _inst_1)))
+Case conversion may be inaccurate. Consider using '#align subgroup.index_eq_one Subgroup.index_eq_oneₓ'. -/
 @[simp, to_additive index_eq_one]
 theorem index_eq_one : H.index = 1 ↔ H = ⊤ :=
   ⟨fun h =>
@@ -789,23 +806,30 @@ theorem index_eq_one : H.index = 1 ↔ H = ⊤ :=
     fun h => (congr_arg index h).trans index_top⟩
 #align subgroup.index_eq_one Subgroup.index_eq_one
 #align add_subgroup.index_eq_one AddSubgroup.index_eq_one
--/
 
-#print Subgroup.relindex_eq_one /-
+/- warning: subgroup.relindex_eq_one -> Subgroup.relindex_eq_one is a dubious translation:
+lean 3 declaration is
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1}, Iff (Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 H K) (OfNat.ofNat.{0} Nat 1 (OfNat.mk.{0} Nat 1 (One.one.{0} Nat Nat.hasOne)))) (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toLE.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (SetLike.partialOrder.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)))) K H)
+but is expected to have type
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1}, Iff (Eq.{1} Nat (Subgroup.relindex.{u1} G _inst_1 H K) (OfNat.ofNat.{0} Nat 1 (instOfNatNat 1))) (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toLE.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (CompleteSemilatticeInf.toPartialOrder.{u1} (Subgroup.{u1} G _inst_1) (CompleteLattice.toCompleteSemilatticeInf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instCompleteLatticeSubgroup.{u1} G _inst_1))))) K H)
+Case conversion may be inaccurate. Consider using '#align subgroup.relindex_eq_one Subgroup.relindex_eq_oneₓ'. -/
 @[simp, to_additive relindex_eq_one]
 theorem relindex_eq_one : H.relindex K = 1 ↔ K ≤ H :=
   index_eq_one.trans subgroupOf_eq_top
 #align subgroup.relindex_eq_one Subgroup.relindex_eq_one
 #align add_subgroup.relindex_eq_one AddSubgroup.relindex_eq_one
--/
 
-#print Subgroup.card_eq_one /-
+/- warning: subgroup.card_eq_one -> Subgroup.card_eq_one is a dubious translation:
+lean 3 declaration is
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1}, Iff (Eq.{1} Nat (Nat.card.{u1} (coeSort.{succ u1, succ (succ u1)} (Subgroup.{u1} G _inst_1) Type.{u1} (SetLike.hasCoeToSort.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)) H)) (OfNat.ofNat.{0} Nat 1 (OfNat.mk.{0} Nat 1 (One.one.{0} Nat Nat.hasOne)))) (Eq.{succ u1} (Subgroup.{u1} G _inst_1) H (Bot.bot.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.hasBot.{u1} G _inst_1)))
+but is expected to have type
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1}, Iff (Eq.{1} Nat (Nat.card.{u1} (Subtype.{succ u1} G (fun (x : G) => Membership.mem.{u1, u1} G (Subgroup.{u1} G _inst_1) (SetLike.instMembership.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.instSetLikeSubgroup.{u1} G _inst_1)) x H))) (OfNat.ofNat.{0} Nat 1 (instOfNatNat 1))) (Eq.{succ u1} (Subgroup.{u1} G _inst_1) H (Bot.bot.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instBotSubgroup.{u1} G _inst_1)))
+Case conversion may be inaccurate. Consider using '#align subgroup.card_eq_one Subgroup.card_eq_oneₓ'. -/
 @[simp, to_additive card_eq_one]
 theorem card_eq_one : Nat.card H = 1 ↔ H = ⊥ :=
   H.relindex_bot_left ▸ relindex_eq_one.trans le_bot_iff
 #align subgroup.card_eq_one Subgroup.card_eq_one
 #align add_subgroup.card_eq_one AddSubgroup.card_eq_one
--/
 
 #print Subgroup.index_ne_zero_of_finite /-
 @[to_additive]
@@ -827,13 +851,17 @@ noncomputable def fintypeOfIndexNeZero (hH : H.index ≠ 0) : Fintype (G ⧸ H)
 #align add_subgroup.fintype_of_index_ne_zero AddSubgroup.fintypeOfIndexNeZero
 -/
 
-#print Subgroup.one_lt_index_of_ne_top /-
+/- warning: subgroup.one_lt_index_of_ne_top -> Subgroup.one_lt_index_of_ne_top is a dubious translation:
+lean 3 declaration is
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} [_inst_2 : Finite.{succ u1} (HasQuotient.Quotient.{u1, u1} G (Subgroup.{u1} G _inst_1) (QuotientGroup.Subgroup.hasQuotient.{u1} G _inst_1) H)], (Ne.{succ u1} (Subgroup.{u1} G _inst_1) H (Top.top.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.hasTop.{u1} G _inst_1))) -> (LT.lt.{0} Nat Nat.hasLt (OfNat.ofNat.{0} Nat 1 (OfNat.mk.{0} Nat 1 (One.one.{0} Nat Nat.hasOne))) (Subgroup.index.{u1} G _inst_1 H))
+but is expected to have type
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} [_inst_2 : Finite.{succ u1} (HasQuotient.Quotient.{u1, u1} G (Subgroup.{u1} G _inst_1) (QuotientGroup.instHasQuotientSubgroup.{u1} G _inst_1) H)], (Ne.{succ u1} (Subgroup.{u1} G _inst_1) H (Top.top.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instTopSubgroup.{u1} G _inst_1))) -> (LT.lt.{0} Nat instLTNat (OfNat.ofNat.{0} Nat 1 (instOfNatNat 1)) (Subgroup.index.{u1} G _inst_1 H))
+Case conversion may be inaccurate. Consider using '#align subgroup.one_lt_index_of_ne_top Subgroup.one_lt_index_of_ne_topₓ'. -/
 @[to_additive one_lt_index_of_ne_top]
 theorem one_lt_index_of_ne_top [Finite (G ⧸ H)] (hH : H ≠ ⊤) : 1 < H.index :=
   Nat.one_lt_iff_ne_zero_and_ne_one.mpr ⟨index_ne_zero_of_finite, mt index_eq_one.mp hH⟩
 #align subgroup.one_lt_index_of_ne_top Subgroup.one_lt_index_of_ne_top
 #align add_subgroup.one_lt_index_of_ne_top AddSubgroup.one_lt_index_of_ne_top
--/
 
 section FiniteIndex
 
@@ -896,17 +924,26 @@ instance [FiniteIndex H] [FiniteIndex K] : FiniteIndex (H ⊓ K) :=
 
 variable {H K}
 
-#print Subgroup.finiteIndex_of_le /-
+/- warning: subgroup.finite_index_of_le -> Subgroup.finiteIndex_of_le is a dubious translation:
+lean 3 declaration is
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1} [_inst_2 : Subgroup.FiniteIndex.{u1} G _inst_1 H], (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toLE.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (SetLike.partialOrder.{u1, u1} (Subgroup.{u1} G _inst_1) G (Subgroup.setLike.{u1} G _inst_1)))) H K) -> (Subgroup.FiniteIndex.{u1} G _inst_1 K)
+but is expected to have type
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {H : Subgroup.{u1} G _inst_1} {K : Subgroup.{u1} G _inst_1} [_inst_2 : Subgroup.FiniteIndex.{u1} G _inst_1 H], (LE.le.{u1} (Subgroup.{u1} G _inst_1) (Preorder.toLE.{u1} (Subgroup.{u1} G _inst_1) (PartialOrder.toPreorder.{u1} (Subgroup.{u1} G _inst_1) (CompleteSemilatticeInf.toPartialOrder.{u1} (Subgroup.{u1} G _inst_1) (CompleteLattice.toCompleteSemilatticeInf.{u1} (Subgroup.{u1} G _inst_1) (Subgroup.instCompleteLatticeSubgroup.{u1} G _inst_1))))) H K) -> (Subgroup.FiniteIndex.{u1} G _inst_1 K)
+Case conversion may be inaccurate. Consider using '#align subgroup.finite_index_of_le Subgroup.finiteIndex_of_leₓ'. -/
 @[to_additive]
 theorem finiteIndex_of_le [FiniteIndex H] (h : H ≤ K) : FiniteIndex K :=
   ⟨ne_zero_of_dvd_ne_zero FiniteIndex.finiteIndex (index_dvd_of_le h)⟩
 #align subgroup.finite_index_of_le Subgroup.finiteIndex_of_le
 #align add_subgroup.finite_index_of_le AddSubgroup.finiteIndex_of_le
--/
 
 variable (H K)
 
-#print Subgroup.finiteIndex_ker /-
+/- warning: subgroup.finite_index_ker -> Subgroup.finiteIndex_ker is a dubious translation:
+lean 3 declaration is
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {G' : Type.{u2}} [_inst_2 : Group.{u2} G'] (f : MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) [_inst_3 : Finite.{succ u2} (coeSort.{succ u2, succ (succ u2)} (Subgroup.{u2} G' _inst_2) Type.{u2} (SetLike.hasCoeToSort.{u2, u2} (Subgroup.{u2} G' _inst_2) G' (Subgroup.setLike.{u2} G' _inst_2)) (MonoidHom.range.{u1, u2} G _inst_1 G' _inst_2 f))], Subgroup.FiniteIndex.{u1} G _inst_1 (MonoidHom.ker.{u1, u2} G _inst_1 G' (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) f)
+but is expected to have type
+  forall {G : Type.{u1}} [_inst_1 : Group.{u1} G] {G' : Type.{u2}} [_inst_2 : Group.{u2} G'] (f : MonoidHom.{u1, u2} G G' (Monoid.toMulOneClass.{u1} G (DivInvMonoid.toMonoid.{u1} G (Group.toDivInvMonoid.{u1} G _inst_1))) (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2)))) [_inst_3 : Finite.{succ u2} (Subtype.{succ u2} G' (fun (x : G') => Membership.mem.{u2, u2} G' (Subgroup.{u2} G' _inst_2) (SetLike.instMembership.{u2, u2} (Subgroup.{u2} G' _inst_2) G' (Subgroup.instSetLikeSubgroup.{u2} G' _inst_2)) x (MonoidHom.range.{u1, u2} G _inst_1 G' _inst_2 f)))], Subgroup.FiniteIndex.{u1} G _inst_1 (MonoidHom.ker.{u1, u2} G _inst_1 G' (Monoid.toMulOneClass.{u2} G' (DivInvMonoid.toMonoid.{u2} G' (Group.toDivInvMonoid.{u2} G' _inst_2))) f)
+Case conversion may be inaccurate. Consider using '#align subgroup.finite_index_ker Subgroup.finiteIndex_kerₓ'. -/
 @[to_additive]
 instance finiteIndex_ker {G' : Type _} [Group G'] (f : G →* G') [Finite f.range] :
     f.ker.FiniteIndex :=
@@ -914,7 +951,6 @@ instance finiteIndex_ker {G' : Type _} [Group G'] (f : G →* G') [Finite f.rang
     (Finite.of_equiv f.range (QuotientGroup.quotientKerEquivRange f).symm)
 #align subgroup.finite_index_ker Subgroup.finiteIndex_ker
 #align add_subgroup.finite_index_ker AddSubgroup.finiteIndex_ker
--/
 
 #print Subgroup.finiteIndex_normalCore /-
 instance finiteIndex_normalCore [H.FiniteIndex] : H.normalCore.FiniteIndex :=

mathlib commit https://github.com/leanprover-community/mathlib/commit/bd9851ca476957ea4549eb19b40e7b5ade9428cc

@@ -180,7 +180,7 @@ of `b * a` and `b` belong to `H`. -/
 for all `b`, exactly one of `b + a` and `b` belong to `H`."]
 theorem index_eq_two_iff : H.index = 2 ↔ ∃ a, ∀ b, Xor' (b * a ∈ H) (b ∈ H) := by
   simp only [index, Nat.card_eq_two_iff' ((1 : G) : G ⧸ H), ExistsUnique, inv_mem_iff,
-    QuotientGroup.exists_mk, QuotientGroup.forall_mk, Ne.def, QuotientGroup.eq, mul_one,
+    QuotientGroup.exists_mk, QuotientGroup.forall_mk, Ne, QuotientGroup.eq, mul_one,
     xor_iff_iff_not]
   refine'
     exists_congr fun a => ⟨fun ha b => ⟨fun hba hb => _, fun hb => _⟩, fun ha => ⟨_, fun b hb => _⟩⟩

Homogenises porting notes via capitalisation and addition of whitespace.

It makes the following changes:

• converts "--porting note" into "-- Porting note";
• converts "porting note" into "Porting note".

@@ -217,7 +217,7 @@ theorem sq_mem_of_index_two (h : H.index = 2) (a : G) : a ^ 2 ∈ H :=
 
 variable (H K)
 
---porting note: had to replace `Cardinal.toNat_eq_one_iff_unique` with `Nat.card_eq_one_iff_unique`
+-- Porting note: had to replace `Cardinal.toNat_eq_one_iff_unique` with `Nat.card_eq_one_iff_unique`
 @[to_additive (attr := simp)]
 theorem index_top : (⊤ : Subgroup G).index = 1 :=
   Nat.card_eq_one_iff_unique.mpr ⟨QuotientGroup.subsingleton_quotient_top, ⟨1⟩⟩
@@ -481,7 +481,7 @@ theorem index_iInf_le {ι : Type*} [Fintype ι] (f : ι → Subgroup G) :
 #align subgroup.index_infi_le Subgroup.index_iInf_le
 #align add_subgroup.index_infi_le AddSubgroup.index_iInf_le
 
---porting note: had to replace `Cardinal.toNat_eq_one_iff_unique` with `Nat.card_eq_one_iff_unique`
+-- Porting note: had to replace `Cardinal.toNat_eq_one_iff_unique` with `Nat.card_eq_one_iff_unique`
 @[to_additive (attr := simp) index_eq_one]
 theorem index_eq_one : H.index = 1 ↔ H = ⊤ :=
   ⟨fun h =>
@@ -510,7 +510,7 @@ theorem index_ne_zero_of_finite [hH : Finite (G ⧸ H)] : H.index ≠ 0 := by
 #align subgroup.index_ne_zero_of_finite Subgroup.index_ne_zero_of_finite
 #align add_subgroup.index_ne_zero_of_finite AddSubgroup.index_ne_zero_of_finite
 
---porting note: changed due to error with `Cardinal.toNat_apply_of_aleph0_le`
+-- Porting note: changed due to error with `Cardinal.toNat_apply_of_aleph0_le`
 /-- Finite index implies finite quotient. -/
 @[to_additive "Finite index implies finite quotient."]
 noncomputable def fintypeOfIndexNeZero (hH : H.index ≠ 0) : Fintype (G ⧸ H) :=
@@ -559,7 +559,7 @@ theorem finiteIndex_of_finite_quotient [Finite (G ⧸ H)] : FiniteIndex H :=
 #align subgroup.finite_index_of_finite_quotient Subgroup.finiteIndex_of_finite_quotient
 #align add_subgroup.finite_index_of_finite_quotient AddSubgroup.finiteIndex_of_finite_quotient
 
---porting note: had to manually provide finite instance for quotient when it should be automatic
+-- Porting note: had to manually provide finite instance for quotient when it should be automatic
 @[to_additive]
 instance (priority := 100) finiteIndex_of_finite [Finite G] : FiniteIndex H :=
   @finiteIndex_of_finite_quotient _ _ H (Quotient.finite _)

doc(GroupTheory.Index): update main definitions to use relindex_mul_index.

@@ -27,7 +27,7 @@ Several theorems proved in this file are known as Lagrange's theorem.
 - `card_mul_index` : `Nat.card H * H.index = Nat.card G`
 - `index_mul_card` : `H.index * Fintype.card H = Fintype.card G`
 - `index_dvd_card` : `H.index ∣ Fintype.card G`
-- `index_eq_mul_of_le` : If `H ≤ K`, then `H.index = K.index * (H.subgroupOf K).index`
+- `relindex_mul_index` : If `H ≤ K`, then `H.relindex K * K.index = H.index`
 - `index_dvd_of_le` : If `H ≤ K`, then `K.index ∣ H.index`
 - `relindex_mul_relindex` : `relindex` is multiplicative in towers
 

We remove all possible occurences of Type _ and Sort _ in favor of Type* and Sort*.

This has nice performance benefits.

@@ -38,7 +38,7 @@ namespace Subgroup
 
 open BigOperators Cardinal
 
-variable {G : Type _} [Group G] (H K L : Subgroup G)
+variable {G : Type*} [Group G] (H K L : Subgroup G)
 
 /-- The index of a subgroup as a natural number, and returns 0 if the index is infinite. -/
 @[to_additive "The index of a subgroup as a natural number,
@@ -58,7 +58,7 @@ noncomputable def relindex : ℕ :=
 #align add_subgroup.relindex AddSubgroup.relindex
 
 @[to_additive]
-theorem index_comap_of_surjective {G' : Type _} [Group G'] {f : G' →* G}
+theorem index_comap_of_surjective {G' : Type*} [Group G'] {f : G' →* G}
     (hf : Function.Surjective f) : (H.comap f).index = H.index := by
   letI := QuotientGroup.leftRel H
   letI := QuotientGroup.leftRel (H.comap f)
@@ -77,7 +77,7 @@ theorem index_comap_of_surjective {G' : Type _} [Group G'] {f : G' →* G}
 #align add_subgroup.index_comap_of_surjective AddSubgroup.index_comap_of_surjective
 
 @[to_additive]
-theorem index_comap {G' : Type _} [Group G'] (f : G' →* G) :
+theorem index_comap {G' : Type*} [Group G'] (f : G' →* G) :
     (H.comap f).index = H.relindex f.range :=
   Eq.trans (congr_arg index (by rfl))
     ((H.subgroupOf f.range).index_comap_of_surjective f.rangeRestrict_surjective)
@@ -85,7 +85,7 @@ theorem index_comap {G' : Type _} [Group G'] (f : G' →* G) :
 #align add_subgroup.index_comap AddSubgroup.index_comap
 
 @[to_additive]
-theorem relindex_comap {G' : Type _} [Group G'] (f : G' →* G) (K : Subgroup G') :
+theorem relindex_comap {G' : Type*} [Group G'] (f : G' →* G) (K : Subgroup G') :
     relindex (comap f H) K = relindex H (map f K) := by
   rw [relindex, subgroupOf, comap_comap, index_comap, ← f.map_range, K.subtype_range]
 #align subgroup.relindex_comap Subgroup.relindex_comap
@@ -293,7 +293,7 @@ theorem card_mul_index : Nat.card H * H.index = Nat.card G := by
 #align add_subgroup.card_mul_index AddSubgroup.card_mul_index
 
 @[to_additive]
-theorem nat_card_dvd_of_injective {G H : Type _} [Group G] [Group H] (f : G →* H)
+theorem nat_card_dvd_of_injective {G H : Type*} [Group G] [Group H] (f : G →* H)
     (hf : Function.Injective f) : Nat.card G ∣ Nat.card H := by
   rw [Nat.card_congr (MonoidHom.ofInjective hf).toEquiv]
   exact Dvd.intro f.range.index f.range.card_mul_index
@@ -307,7 +307,7 @@ theorem nat_card_dvd_of_le (hHK : H ≤ K) : Nat.card H ∣ Nat.card K :=
 #align add_subgroup.nat_card_dvd_of_le AddSubgroup.nat_card_dvd_of_le
 
 @[to_additive]
-theorem nat_card_dvd_of_surjective {G H : Type _} [Group G] [Group H] (f : G →* H)
+theorem nat_card_dvd_of_surjective {G H : Type*} [Group G] [Group H] (f : G →* H)
     (hf : Function.Surjective f) : Nat.card H ∣ Nat.card G := by
   rw [← Nat.card_congr (QuotientGroup.quotientKerEquivOfSurjective f hf).toEquiv]
   exact Dvd.intro_left (Nat.card f.ker) f.ker.card_mul_index
@@ -315,21 +315,21 @@ theorem nat_card_dvd_of_surjective {G H : Type _} [Group G] [Group H] (f : G →
 #align add_subgroup.nat_card_dvd_of_surjective AddSubgroup.nat_card_dvd_of_surjective
 
 @[to_additive]
-theorem card_dvd_of_surjective {G H : Type _} [Group G] [Group H] [Fintype G] [Fintype H]
+theorem card_dvd_of_surjective {G H : Type*} [Group G] [Group H] [Fintype G] [Fintype H]
     (f : G →* H) (hf : Function.Surjective f) : Fintype.card H ∣ Fintype.card G := by
   simp only [← Nat.card_eq_fintype_card, nat_card_dvd_of_surjective f hf]
 #align subgroup.card_dvd_of_surjective Subgroup.card_dvd_of_surjective
 #align add_subgroup.card_dvd_of_surjective AddSubgroup.card_dvd_of_surjective
 
 @[to_additive]
-theorem index_map {G' : Type _} [Group G'] (f : G →* G') :
+theorem index_map {G' : Type*} [Group G'] (f : G →* G') :
     (H.map f).index = (H ⊔ f.ker).index * f.range.index := by
   rw [← comap_map_eq, index_comap, relindex_mul_index (H.map_le_range f)]
 #align subgroup.index_map Subgroup.index_map
 #align add_subgroup.index_map AddSubgroup.index_map
 
 @[to_additive]
-theorem index_map_dvd {G' : Type _} [Group G'] {f : G →* G'} (hf : Function.Surjective f) :
+theorem index_map_dvd {G' : Type*} [Group G'] {f : G →* G'} (hf : Function.Surjective f) :
     (H.map f).index ∣ H.index := by
   rw [index_map, f.range_top_of_surjective hf, index_top, mul_one]
   exact index_dvd_of_le le_sup_left
@@ -337,7 +337,7 @@ theorem index_map_dvd {G' : Type _} [Group G'] {f : G →* G'} (hf : Function.Su
 #align add_subgroup.index_map_dvd AddSubgroup.index_map_dvd
 
 @[to_additive]
-theorem dvd_index_map {G' : Type _} [Group G'] {f : G →* G'} (hf : f.ker ≤ H) :
+theorem dvd_index_map {G' : Type*} [Group G'] {f : G →* G'} (hf : f.ker ≤ H) :
     H.index ∣ (H.map f).index := by
   rw [index_map, sup_of_le_left hf]
   apply dvd_mul_right
@@ -345,7 +345,7 @@ theorem dvd_index_map {G' : Type _} [Group G'] {f : G →* G'} (hf : f.ker ≤ H
 #align add_subgroup.dvd_index_map AddSubgroup.dvd_index_map
 
 @[to_additive]
-theorem index_map_eq {G' : Type _} [Group G'] {f : G →* G'} (hf1 : Function.Surjective f)
+theorem index_map_eq {G' : Type*} [Group G'] {f : G →* G'} (hf1 : Function.Surjective f)
     (hf2 : f.ker ≤ H) : (H.map f).index = H.index :=
   Nat.dvd_antisymm (H.index_map_dvd hf1) (H.dvd_index_map hf2)
 #align subgroup.index_map_eq Subgroup.index_map_eq
@@ -447,7 +447,7 @@ theorem index_inf_le : (H ⊓ K).index ≤ H.index * K.index := by
 #align add_subgroup.index_inf_le AddSubgroup.index_inf_le
 
 @[to_additive]
-theorem relindex_iInf_ne_zero {ι : Type _} [_hι : Finite ι] {f : ι → Subgroup G}
+theorem relindex_iInf_ne_zero {ι : Type*} [_hι : Finite ι] {f : ι → Subgroup G}
     (hf : ∀ i, (f i).relindex L ≠ 0) : (⨅ i, f i).relindex L ≠ 0 :=
   haveI := Fintype.ofFinite ι
   (Finset.prod_ne_zero_iff.mpr fun i _hi => hf i) ∘
@@ -457,7 +457,7 @@ theorem relindex_iInf_ne_zero {ι : Type _} [_hι : Finite ι] {f : ι → Subgr
 #align add_subgroup.relindex_infi_ne_zero AddSubgroup.relindex_iInf_ne_zero
 
 @[to_additive]
-theorem relindex_iInf_le {ι : Type _} [Fintype ι] (f : ι → Subgroup G) :
+theorem relindex_iInf_le {ι : Type*} [Fintype ι] (f : ι → Subgroup G) :
     (⨅ i, f i).relindex L ≤ ∏ i, (f i).relindex L :=
   le_of_le_of_eq
     (Finite.card_le_of_embedding' (quotientiInfSubgroupOfEmbedding f L) fun h =>
@@ -468,7 +468,7 @@ theorem relindex_iInf_le {ι : Type _} [Fintype ι] (f : ι → Subgroup G) :
 #align add_subgroup.relindex_infi_le AddSubgroup.relindex_iInf_le
 
 @[to_additive]
-theorem index_iInf_ne_zero {ι : Type _} [Finite ι] {f : ι → Subgroup G}
+theorem index_iInf_ne_zero {ι : Type*} [Finite ι] {f : ι → Subgroup G}
     (hf : ∀ i, (f i).index ≠ 0) : (⨅ i, f i).index ≠ 0 := by
   simp_rw [← relindex_top_right] at hf ⊢
   exact relindex_iInf_ne_zero hf
@@ -476,7 +476,7 @@ theorem index_iInf_ne_zero {ι : Type _} [Finite ι] {f : ι → Subgroup G}
 #align add_subgroup.index_infi_ne_zero AddSubgroup.index_iInf_ne_zero
 
 @[to_additive]
-theorem index_iInf_le {ι : Type _} [Fintype ι] (f : ι → Subgroup G) :
+theorem index_iInf_le {ι : Type*} [Fintype ι] (f : ι → Subgroup G) :
     (⨅ i, f i).index ≤ ∏ i, (f i).index := by simp_rw [← relindex_top_right, relindex_iInf_le]
 #align subgroup.index_infi_le Subgroup.index_iInf_le
 #align add_subgroup.index_infi_le AddSubgroup.index_iInf_le
@@ -535,7 +535,7 @@ class FiniteIndex : Prop where
 #align subgroup.finite_index Subgroup.FiniteIndex
 
 /-- Typeclass for finite index subgroups. -/
-class _root_.AddSubgroup.FiniteIndex {G : Type _} [AddGroup G] (H : AddSubgroup G) : Prop where
+class _root_.AddSubgroup.FiniteIndex {G : Type*} [AddGroup G] (H : AddSubgroup G) : Prop where
   /-- The additive subgroup has finite index -/
   finiteIndex : H.index ≠ 0
 #align add_subgroup.finite_index AddSubgroup.FiniteIndex
@@ -585,7 +585,7 @@ theorem finiteIndex_of_le [FiniteIndex H] (h : H ≤ K) : FiniteIndex K :=
 variable (H K)
 
 @[to_additive]
-instance finiteIndex_ker {G' : Type _} [Group G'] (f : G →* G') [Finite f.range] :
+instance finiteIndex_ker {G' : Type*} [Group G'] (f : G →* G') [Finite f.range] :
     f.ker.FiniteIndex :=
   @finiteIndex_of_finite_quotient G _ f.ker
     (Finite.of_equiv f.range (QuotientGroup.quotientKerEquivRange f).symm)

@@ -96,7 +96,7 @@ variable {H K L}
 @[to_additive relindex_mul_index]
 theorem relindex_mul_index (h : H ≤ K) : H.relindex K * K.index = H.index :=
   ((mul_comm _ _).trans (Cardinal.toNat_mul _ _).symm).trans
-    (congr_arg Cardinal.toNat (Equiv.cardinal_eq (quotientEquivProdOfLe h))).symm
+    (congr_arg Cardinal.toNat (Equiv.cardinal_eq (quotientEquivProdOfLE h))).symm
 #align subgroup.relindex_mul_index Subgroup.relindex_mul_index
 #align add_subgroup.relindex_mul_index AddSubgroup.relindex_mul_index
 
@@ -381,7 +381,7 @@ theorem relindex_eq_zero_of_le_left (hHK : H ≤ K) (hKL : K.relindex L = 0) : H
 
 @[to_additive]
 theorem relindex_eq_zero_of_le_right (hKL : K ≤ L) (hHK : H.relindex K = 0) : H.relindex L = 0 :=
-  Finite.card_eq_zero_of_embedding (quotientSubgroupOfEmbeddingOfLe H hKL) hHK
+  Finite.card_eq_zero_of_embedding (quotientSubgroupOfEmbeddingOfLE H hKL) hHK
 #align subgroup.relindex_eq_zero_of_le_right Subgroup.relindex_eq_zero_of_le_right
 #align add_subgroup.relindex_eq_zero_of_le_right AddSubgroup.relindex_eq_zero_of_le_right
 
@@ -401,7 +401,7 @@ theorem relindex_le_of_le_left (hHK : H ≤ K) (hHL : H.relindex L ≠ 0) :
 @[to_additive]
 theorem relindex_le_of_le_right (hKL : K ≤ L) (hHL : H.relindex L ≠ 0) :
     H.relindex K ≤ H.relindex L :=
-  Finite.card_le_of_embedding' (quotientSubgroupOfEmbeddingOfLe H hKL) fun h => (hHL h).elim
+  Finite.card_le_of_embedding' (quotientSubgroupOfEmbeddingOfLE H hKL) fun h => (hHL h).elim
 #align subgroup.relindex_le_of_le_right Subgroup.relindex_le_of_le_right
 #align add_subgroup.relindex_le_of_le_right AddSubgroup.relindex_le_of_le_right
 

• depends on: #5966

Co-authored-by: Eric Wieser <wieser.eric@gmail.com> Co-authored-by: Scott Morrison <scott.morrison@gmail.com>

@@ -2,16 +2,13 @@
 Copyright (c) 2021 Thomas Browning. All rights reserved.
 Released under Apache 2.0 license as described in the file LICENSE.
 Authors: Thomas Browning
-
-! This file was ported from Lean 3 source module group_theory.index
-! leanprover-community/mathlib commit dc6c365e751e34d100e80fe6e314c3c3e0fd2988
-! Please do not edit these lines, except to modify the commit id
-! if you have ported upstream changes.
 -/
 import Mathlib.Data.Finite.Card
 import Mathlib.GroupTheory.Finiteness
 import Mathlib.GroupTheory.GroupAction.Quotient
 
+#align_import group_theory.index from "leanprover-community/mathlib"@"dc6c365e751e34d100e80fe6e314c3c3e0fd2988"
+
 /-!
 # Index of a Subgroup
 

Changes are of the form

• some_tactic at h⊢ -> some_tactic at h ⊢
• some_tactic at h -> some_tactic at h

@@ -420,7 +420,7 @@ theorem relindex_ne_zero_trans (hHK : H.relindex K ≠ 0) (hKL : K.relindex L 
 theorem relindex_inf_ne_zero (hH : H.relindex L ≠ 0) (hK : K.relindex L ≠ 0) :
     (H ⊓ K).relindex L ≠ 0 := by
   replace hH : H.relindex (K ⊓ L) ≠ 0 := mt (relindex_eq_zero_of_le_right inf_le_right) hH
-  rw [← inf_relindex_right] at hH hK⊢
+  rw [← inf_relindex_right] at hH hK ⊢
   rw [inf_assoc]
   exact relindex_ne_zero_trans hH hK
 #align subgroup.relindex_inf_ne_zero Subgroup.relindex_inf_ne_zero
@@ -428,7 +428,7 @@ theorem relindex_inf_ne_zero (hH : H.relindex L ≠ 0) (hK : K.relindex L ≠ 0)
 
 @[to_additive]
 theorem index_inf_ne_zero (hH : H.index ≠ 0) (hK : K.index ≠ 0) : (H ⊓ K).index ≠ 0 := by
-  rw [← relindex_top_right] at hH hK⊢
+  rw [← relindex_top_right] at hH hK ⊢
   exact relindex_inf_ne_zero hH hK
 #align subgroup.index_inf_ne_zero Subgroup.index_inf_ne_zero
 #align add_subgroup.index_inf_ne_zero AddSubgroup.index_inf_ne_zero
@@ -473,7 +473,7 @@ theorem relindex_iInf_le {ι : Type _} [Fintype ι] (f : ι → Subgroup G) :
 @[to_additive]
 theorem index_iInf_ne_zero {ι : Type _} [Finite ι] {f : ι → Subgroup G}
     (hf : ∀ i, (f i).index ≠ 0) : (⨅ i, f i).index ≠ 0 := by
-  simp_rw [← relindex_top_right] at hf⊢
+  simp_rw [← relindex_top_right] at hf ⊢
   exact relindex_iInf_ne_zero hf
 #align subgroup.index_infi_ne_zero Subgroup.index_iInf_ne_zero
 #align add_subgroup.index_infi_ne_zero AddSubgroup.index_iInf_ne_zero

Please refer to this Zulip thread: https://leanprover.zulipchat.com/#narrow/stream/287929-mathlib4/topic/Naming.20convention/near/357712556

@@ -602,12 +602,12 @@ instance finiteIndex_normalCore [H.FiniteIndex] : H.normalCore.FiniteIndex := by
 
 variable (G)
 
-instance finiteIndex_center [Finite (commutatorSet G)] [Group.Fg G] : FiniteIndex (center G) := by
+instance finiteIndex_center [Finite (commutatorSet G)] [Group.FG G] : FiniteIndex (center G) := by
   obtain ⟨S, -, hS⟩ := Group.rank_spec G
   exact ⟨mt (Finite.card_eq_zero_of_embedding (quotientCenterEmbedding hS)) Finite.card_pos.ne'⟩
 #align subgroup.finite_index_center Subgroup.finiteIndex_center
 
-theorem index_center_le_pow [Finite (commutatorSet G)] [Group.Fg G] :
+theorem index_center_le_pow [Finite (commutatorSet G)] [Group.FG G] :
     (center G).index ≤ Nat.card (commutatorSet G) ^ Group.rank G := by
   obtain ⟨S, hS1, hS2⟩ := Group.rank_spec G
   rw [← hS1, ← Fintype.card_coe, ← Nat.card_eq_fintype_card, ← Finset.coe_sort_coe, ← Nat.card_fun]

As discussed on Zulip

Renames

• supₛ → sSup
• infₛ → sInf
• supᵢ → iSup
• infᵢ → iInf
• bsupₛ → bsSup
• binfₛ → bsInf
• bsupᵢ → biSup
• binfᵢ → biInf
• csupₛ → csSup
• cinfₛ → csInf
• csupᵢ → ciSup
• cinfᵢ → ciInf
• unionₛ → sUnion
• interₛ → sInter
• unionᵢ → iUnion
• interᵢ → iInter
• bunionₛ → bsUnion
• binterₛ → bsInter
• bunionᵢ → biUnion
• binterᵢ → biInter

Co-authored-by: Parcly Taxel <reddeloostw@gmail.com>

@@ -450,39 +450,39 @@ theorem index_inf_le : (H ⊓ K).index ≤ H.index * K.index := by
 #align add_subgroup.index_inf_le AddSubgroup.index_inf_le
 
 @[to_additive]
-theorem relindex_infᵢ_ne_zero {ι : Type _} [_hι : Finite ι] {f : ι → Subgroup G}
+theorem relindex_iInf_ne_zero {ι : Type _} [_hι : Finite ι] {f : ι → Subgroup G}
     (hf : ∀ i, (f i).relindex L ≠ 0) : (⨅ i, f i).relindex L ≠ 0 :=
   haveI := Fintype.ofFinite ι
   (Finset.prod_ne_zero_iff.mpr fun i _hi => hf i) ∘
     Nat.card_pi.symm.trans ∘
-      Finite.card_eq_zero_of_embedding (quotientInfᵢSubgroupOfEmbedding f L)
-#align subgroup.relindex_infi_ne_zero Subgroup.relindex_infᵢ_ne_zero
-#align add_subgroup.relindex_infi_ne_zero AddSubgroup.relindex_infᵢ_ne_zero
+      Finite.card_eq_zero_of_embedding (quotientiInfSubgroupOfEmbedding f L)
+#align subgroup.relindex_infi_ne_zero Subgroup.relindex_iInf_ne_zero
+#align add_subgroup.relindex_infi_ne_zero AddSubgroup.relindex_iInf_ne_zero
 
 @[to_additive]
-theorem relindex_infᵢ_le {ι : Type _} [Fintype ι] (f : ι → Subgroup G) :
+theorem relindex_iInf_le {ι : Type _} [Fintype ι] (f : ι → Subgroup G) :
     (⨅ i, f i).relindex L ≤ ∏ i, (f i).relindex L :=
   le_of_le_of_eq
-    (Finite.card_le_of_embedding' (quotientInfᵢSubgroupOfEmbedding f L) fun h =>
+    (Finite.card_le_of_embedding' (quotientiInfSubgroupOfEmbedding f L) fun h =>
       let ⟨i, _hi, h⟩ := Finset.prod_eq_zero_iff.mp (Nat.card_pi.symm.trans h)
-      relindex_eq_zero_of_le_left (infᵢ_le f i) h)
+      relindex_eq_zero_of_le_left (iInf_le f i) h)
     Nat.card_pi
-#align subgroup.relindex_infi_le Subgroup.relindex_infᵢ_le
-#align add_subgroup.relindex_infi_le AddSubgroup.relindex_infᵢ_le
+#align subgroup.relindex_infi_le Subgroup.relindex_iInf_le
+#align add_subgroup.relindex_infi_le AddSubgroup.relindex_iInf_le
 
 @[to_additive]
-theorem index_infᵢ_ne_zero {ι : Type _} [Finite ι] {f : ι → Subgroup G}
+theorem index_iInf_ne_zero {ι : Type _} [Finite ι] {f : ι → Subgroup G}
     (hf : ∀ i, (f i).index ≠ 0) : (⨅ i, f i).index ≠ 0 := by
   simp_rw [← relindex_top_right] at hf⊢
-  exact relindex_infᵢ_ne_zero hf
-#align subgroup.index_infi_ne_zero Subgroup.index_infᵢ_ne_zero
-#align add_subgroup.index_infi_ne_zero AddSubgroup.index_infᵢ_ne_zero
+  exact relindex_iInf_ne_zero hf
+#align subgroup.index_infi_ne_zero Subgroup.index_iInf_ne_zero
+#align add_subgroup.index_infi_ne_zero AddSubgroup.index_iInf_ne_zero
 
 @[to_additive]
-theorem index_infᵢ_le {ι : Type _} [Fintype ι] (f : ι → Subgroup G) :
-    (⨅ i, f i).index ≤ ∏ i, (f i).index := by simp_rw [← relindex_top_right, relindex_infᵢ_le]
-#align subgroup.index_infi_le Subgroup.index_infᵢ_le
-#align add_subgroup.index_infi_le AddSubgroup.index_infᵢ_le
+theorem index_iInf_le {ι : Type _} [Fintype ι] (f : ι → Subgroup G) :
+    (⨅ i, f i).index ≤ ∏ i, (f i).index := by simp_rw [← relindex_top_right, relindex_iInf_le]
+#align subgroup.index_infi_le Subgroup.index_iInf_le
+#align add_subgroup.index_infi_le AddSubgroup.index_iInf_le
 
 --porting note: had to replace `Cardinal.toNat_eq_one_iff_unique` with `Nat.card_eq_one_iff_unique`
 @[to_additive (attr := simp) index_eq_one]

This PR puts, with one exception, every single remaining by that lies all by itself on its own line to the previous line, thus matching the current behaviour of start-port.sh. The exception is when the by begins the second or later argument to a tuple or anonymous constructor; see https://github.com/leanprover-community/mathlib4/pull/3825#discussion_r1186702599.

Essentially this is s/\n *by$/ by/g, but with manual editing to satisfy the linter's max-100-char-line requirement. The Python style linter is also modified to catch these "isolated bys".

@@ -65,8 +65,7 @@ theorem index_comap_of_surjective {G' : Type _} [Group G'] {f : G' →* G}
     (hf : Function.Surjective f) : (H.comap f).index = H.index := by
   letI := QuotientGroup.leftRel H
   letI := QuotientGroup.leftRel (H.comap f)
-  have key : ∀ x y : G', Setoid.r x y ↔ Setoid.r (f x) (f y) :=
-    by
+  have key : ∀ x y : G', Setoid.r x y ↔ Setoid.r (f x) (f y) := by
     simp only [QuotientGroup.leftRel_apply]
     exact fun x y => iff_of_eq (congr_arg (· ∈ H) (by rw [f.map_mul, f.map_inv]))
   refine' Cardinal.toNat_congr (Equiv.ofBijective (Quotient.map' f fun x y => (key x y).mp) ⟨_, _⟩)
@@ -362,8 +361,8 @@ theorem index_eq_card [Fintype (G ⧸ H)] : H.index = Fintype.card (G ⧸ H) :=
 #align add_subgroup.index_eq_card AddSubgroup.index_eq_card
 
 @[to_additive index_mul_card]
-theorem index_mul_card [Fintype G] [hH : Fintype H] : H.index * Fintype.card H = Fintype.card G :=
-  by
+theorem index_mul_card [Fintype G] [hH : Fintype H] :
+    H.index * Fintype.card H = Fintype.card G := by
   rw [← relindex_bot_left_eq_card, ← index_bot_eq_card, mul_comm];
     exact relindex_mul_index bot_le
 #align subgroup.index_mul_card Subgroup.index_mul_card

Forward-port #18536

• group_theory.subgroup.basic@1f0096e6caa61e9c849ec2adbd227e960e9dff58..c10e724be91096453ee3db13862b9fb9a992fef2
• group_theory.subgroup.pointwise@59694bd07f0a39c5beccba34bd9f413a160782bf..c10e724be91096453ee3db13862b9fb9a992fef2
• topology.algebra.constructions@d90e4e186f1d18e375dcd4e5b5f6364b01cb3e46..c10e724be91096453ee3db13862b9fb9a992fef2
• topology.algebra.group.basic@dc6c365e751e34d100e80fe6e314c3c3e0fd2988..c10e724be91096453ee3db13862b9fb9a992fef2
• topology.algebra.group_with_zero@48085f140e684306f9e7da907cd5932056d1aded..c10e724be91096453ee3db13862b9fb9a992fef2

@@ -189,10 +189,10 @@ theorem index_eq_two_iff : H.index = 2 ↔ ∃ a, ∀ b, Xor' (b * a ∈ H) (b 
   refine'
     exists_congr fun a => ⟨fun ha b => ⟨fun hba hb => _, fun hb => _⟩, fun ha => ⟨_, fun b hb => _⟩⟩
   · exact ha.1 ((mul_mem_cancel_left hb).1 hba)
-  · exact inv_inv b ▸ ha.2 _ (mt inv_mem_iff.1 hb)
-  · rw [← inv_mem_iff, ← ha, inv_mul_self]
+  · exact inv_inv b ▸ ha.2 _ (mt (inv_mem_iff (x := b)).1 hb)
+  · rw [← inv_mem_iff (x := a), ← ha, inv_mul_self]
     exact one_mem _
-  · rwa [ha, inv_mem_iff]
+  · rwa [ha, inv_mem_iff (x := b)]
 #align subgroup.index_eq_two_iff Subgroup.index_eq_two_iff
 #align add_subgroup.index_eq_two_iff AddSubgroup.index_eq_two_iff
 

Co-authored-by: Moritz Firsching <firsching@google.com> Co-authored-by: Johan Commelin <johan@commelin.net>