PR contents

(last sync)

refactor(*): move all mk_simp_attribute commands to 1 file (#19223)

Diff

@@ -91,8 +91,6 @@ mod_two_add_add_odd_mod_two m odd_one
 @[simp] theorem succ_mod_two_add_mod_two (m : ℕ) : (m + 1) % 2 + m % 2 = 1 :=
 by rw [add_comm, mod_two_add_succ_mod_two]
 
-mk_simp_attribute parity_simps "Simp attribute for lemmas about `even`"
-
 @[simp] theorem not_even_one : ¬ even 1 :=
 by rw even_iff; norm_num

(first ported)

Changes in mathlib3port

mathlib3

mathlib3port

bump to nightly-2024-04-06-08

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

e34029c9

Diff

@@ -3,7 +3,7 @@ Copyright (c) 2019 Jeremy Avigad. All rights reserved.
 Released under Apache 2.0 license as described in the file LICENSE.
 Authors: Jeremy Avigad, Benjamin Davidson
 -/
-import Data.Nat.Modeq
+import Data.Nat.ModEq
 import Algebra.Parity
 
 #align_import data.nat.parity from "leanprover-community/mathlib"@"48fb5b5280e7c81672afc9524185ae994553ebf4"
@@ -246,7 +246,7 @@ theorem Odd.of_mul_right (h : Odd (m * n)) : Odd n :=
 if and only if `m` is even and `n` is positive. -/
 @[parity_simps]
 theorem even_pow : Even (m ^ n) ↔ Even m ∧ n ≠ 0 := by
-  induction' n with n ih <;> simp [*, pow_succ', even_mul]; tauto
+  induction' n with n ih <;> simp [*, pow_succ, even_mul]; tauto
 #align nat.even_pow Nat.even_pow
 -/

bump to nightly-2024-03-17-08

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

22f01ce4

Diff

@@ -392,9 +392,9 @@ theorem bit1_mod_bit0 : bit1 n % bit0 m = bit1 (n % m) :=
   by
   have h₁ := congr_arg bit1 (Nat.div_add_mod n m)
   -- `∀ m n : ℕ, bit0 m * n = bit0 (m * n)` seems to be missing...
-  rw [bit1_add, bit0_eq_two_mul, ← mul_assoc, ← bit0_eq_two_mul] at h₁ 
+  rw [bit1_add, bit0_eq_two_mul, ← mul_assoc, ← bit0_eq_two_mul] at h₁
   have h₂ := Nat.div_add_mod (bit1 n) (bit0 m)
-  rw [bit1_div_bit0] at h₂ 
+  rw [bit1_div_bit0] at h₂
   exact add_left_cancel (h₂.trans h₁.symm)
 #align nat.bit1_mod_bit0 Nat.bit1_mod_bit0
 -/
@@ -443,14 +443,14 @@ theorem iterate_odd (hf : Involutive f) (hn : Odd n) : f^[n] = f :=
 
 #print Function.Involutive.iterate_eq_self /-
 theorem iterate_eq_self (hf : Involutive f) (hne : f ≠ id) : f^[n] = f ↔ Odd n :=
-  ⟨fun H => odd_iff_not_even.2 fun hn => hne <| by rwa [hf.iterate_even hn, eq_comm] at H ,
+  ⟨fun H => odd_iff_not_even.2 fun hn => hne <| by rwa [hf.iterate_even hn, eq_comm] at H,
     hf.iterate_odd⟩
 #align function.involutive.iterate_eq_self Function.Involutive.iterate_eq_self
 -/
 
 #print Function.Involutive.iterate_eq_id /-
 theorem iterate_eq_id (hf : Involutive f) (hne : f ≠ id) : f^[n] = id ↔ Even n :=
-  ⟨fun H => even_iff_not_odd.2 fun hn => hne <| by rwa [hf.iterate_odd hn] at H , hf.iterate_even⟩
+  ⟨fun H => even_iff_not_odd.2 fun hn => hne <| by rwa [hf.iterate_odd hn] at H, hf.iterate_even⟩
 #align function.involutive.iterate_eq_id Function.Involutive.iterate_eq_id
 -/

bump to nightly-2024-01-28-06

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

fe4dd9a4

Diff

@@ -313,14 +313,14 @@ theorem even_mul_succ_self (n : ℕ) : Even (n * (n + 1)) :=
 #align nat.even_mul_succ_self Nat.even_mul_succ_self
 -/
 
-#print Nat.even_mul_self_pred /-
-theorem even_mul_self_pred (n : ℕ) : Even (n * (n - 1)) :=
+#print Nat.even_mul_pred_self /-
+theorem even_mul_pred_self (n : ℕ) : Even (n * (n - 1)) :=
   by
   cases n
   · exact even_zero
   · rw [mul_comm]
     apply even_mul_succ_self
-#align nat.even_mul_self_pred Nat.even_mul_self_pred
+#align nat.even_mul_self_pred Nat.even_mul_pred_self
 -/
 
 #print Nat.two_mul_div_two_of_even /-

bump to nightly-2023-09-24-06

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

5655435f

Diff

@@ -3,8 +3,8 @@ Copyright (c) 2019 Jeremy Avigad. All rights reserved.
 Released under Apache 2.0 license as described in the file LICENSE.
 Authors: Jeremy Avigad, Benjamin Davidson
 -/
-import Mathbin.Data.Nat.Modeq
-import Mathbin.Algebra.Parity
+import Data.Nat.Modeq
+import Algebra.Parity
 
 #align_import data.nat.parity from "leanprover-community/mathlib"@"48fb5b5280e7c81672afc9524185ae994553ebf4"

bump to nightly-2023-07-20-09

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

9c56d0dd

Diff

@@ -2,15 +2,12 @@
 Copyright (c) 2019 Jeremy Avigad. All rights reserved.
 Released under Apache 2.0 license as described in the file LICENSE.
 Authors: Jeremy Avigad, Benjamin Davidson
-
-! This file was ported from Lean 3 source module data.nat.parity
-! leanprover-community/mathlib commit 48fb5b5280e7c81672afc9524185ae994553ebf4
-! Please do not edit these lines, except to modify the commit id
-! if you have ported upstream changes.
 -/
 import Mathbin.Data.Nat.Modeq
 import Mathbin.Algebra.Parity
 
+#align_import data.nat.parity from "leanprover-community/mathlib"@"48fb5b5280e7c81672afc9524185ae994553ebf4"
+
 /-!
 # Parity of natural numbers

bump to nightly-2023-07-04-01

mathlib commit https://github.com/leanprover-community/mathlib/commit/728ef9dbb281241906f25cbeb30f90d83e0bb451

05318d71

Diff

@@ -4,7 +4,7 @@ Released under Apache 2.0 license as described in the file LICENSE.
 Authors: Jeremy Avigad, Benjamin Davidson
 
 ! This file was ported from Lean 3 source module data.nat.parity
-! leanprover-community/mathlib commit a11f9106a169dd302a285019e5165f8ab32ff433
+! leanprover-community/mathlib commit 48fb5b5280e7c81672afc9524185ae994553ebf4
 ! Please do not edit these lines, except to modify the commit id
 ! if you have ported upstream changes.
 -/
@@ -150,10 +150,6 @@ theorem succ_mod_two_add_mod_two (m : ℕ) : (m + 1) % 2 + m % 2 = 1 := by
 #align nat.succ_mod_two_add_mod_two Nat.succ_mod_two_add_mod_two
 -/
 
--- PLEASE REPORT THIS TO MATHPORT DEVS, THIS SHOULD NOT HAPPEN.
--- failed to format: unknown constant 'Lean.Meta._root_.Lean.Parser.Command.registerSimpAttr'
-/-- Simp attribute for lemmas about `even` -/ register_simp_attr parity_simps
-
 #print Nat.not_even_one /-
 @[simp]
 theorem not_even_one : ¬Even 1 := by rw [even_iff] <;> norm_num

bump to nightly-2023-06-13-21

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

829520ac

Diff

@@ -78,9 +78,11 @@ theorem odd_iff_not_even : Odd n ↔ ¬Even n := by rw [not_even_iff, odd_iff]
 #align nat.odd_iff_not_even Nat.odd_iff_not_even
 -/
 
+#print Nat.isCompl_even_odd /-
 theorem isCompl_even_odd : IsCompl {n : ℕ | Even n} {n | Odd n} := by
   simp only [← Set.compl_setOf, isCompl_compl, odd_iff_not_even]
 #align nat.is_compl_even_odd Nat.isCompl_even_odd
+-/
 
 #print Nat.even_or_odd /-
 theorem even_or_odd (n : ℕ) : Even n ∨ Odd n :=
@@ -465,10 +467,12 @@ end Function
 
 variable {R : Type _} [Monoid R] [HasDistribNeg R] {n : ℕ}
 
+#print neg_one_pow_eq_one_iff_even /-
 theorem neg_one_pow_eq_one_iff_even (h : (-1 : R) ≠ 1) : (-1 : R) ^ n = 1 ↔ Even n :=
   ⟨fun h' => of_not_not fun hn => h <| (Odd.neg_one_pow <| odd_iff_not_even.mpr hn).symm.trans h',
     Even.neg_one_pow⟩
 #align neg_one_pow_eq_one_iff_even neg_one_pow_eq_one_iff_even
+-/
 
 #print Odd.mod_even_iff /-
 /-- If `a` is even, then `n` is odd iff `n % a` is odd. -/

bump to nightly-2023-06-08-23

mathlib commit https://github.com/leanprover-community/mathlib/commit/31c24aa72e7b3e5ed97a8412470e904f82b81004

d3cfe2e3

Diff

@@ -148,11 +148,8 @@ theorem succ_mod_two_add_mod_two (m : ℕ) : (m + 1) % 2 + m % 2 = 1 := by
 #align nat.succ_mod_two_add_mod_two Nat.succ_mod_two_add_mod_two
 -/
 
-/- failed to parenthesize: unknown constant 'Lean.Meta._root_.Lean.Parser.Command.registerSimpAttr'
-[PrettyPrinter.parenthesize.input] (Lean.Meta._root_.Lean.Parser.Command.registerSimpAttr
-     [(Command.docComment "/--" "Simp attribute for lemmas about `even` -/")]
-     "register_simp_attr"
-     `parity_simps)-/-- failed to format: unknown constant 'Lean.Meta._root_.Lean.Parser.Command.registerSimpAttr'
+-- PLEASE REPORT THIS TO MATHPORT DEVS, THIS SHOULD NOT HAPPEN.
+-- failed to format: unknown constant 'Lean.Meta._root_.Lean.Parser.Command.registerSimpAttr'
 /-- Simp attribute for lemmas about `even` -/ register_simp_attr parity_simps
 
 #print Nat.not_even_one /-

bump to nightly-2023-06-04-18

mathlib commit https://github.com/leanprover-community/mathlib/commit/5f25c089cb34db4db112556f23c50d12da81b297

3fb4268b

Diff

@@ -78,7 +78,7 @@ theorem odd_iff_not_even : Odd n ↔ ¬Even n := by rw [not_even_iff, odd_iff]
 #align nat.odd_iff_not_even Nat.odd_iff_not_even
 -/
 
-theorem isCompl_even_odd : IsCompl { n : ℕ | Even n } { n | Odd n } := by
+theorem isCompl_even_odd : IsCompl {n : ℕ | Even n} {n | Odd n} := by
   simp only [← Set.compl_setOf, isCompl_compl, odd_iff_not_even]
 #align nat.is_compl_even_odd Nat.isCompl_even_odd

bump to nightly-2023-06-01-16

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

b9c87c70

Diff

@@ -52,7 +52,7 @@ theorem even_iff : Even n ↔ n % 2 = 0 :=
 
 #print Nat.odd_iff /-
 theorem odd_iff : Odd n ↔ n % 2 = 1 :=
-  ⟨fun ⟨m, hm⟩ => by norm_num [hm, add_mod] , fun h =>
+  ⟨fun ⟨m, hm⟩ => by norm_num [hm, add_mod], fun h =>
     ⟨n / 2, (mod_add_div n 2).symm.trans (by rw [h, add_comm])⟩⟩
 #align nat.odd_iff Nat.odd_iff
 -/
@@ -400,9 +400,9 @@ theorem bit1_mod_bit0 : bit1 n % bit0 m = bit1 (n % m) :=
   by
   have h₁ := congr_arg bit1 (Nat.div_add_mod n m)
   -- `∀ m n : ℕ, bit0 m * n = bit0 (m * n)` seems to be missing...
-  rw [bit1_add, bit0_eq_two_mul, ← mul_assoc, ← bit0_eq_two_mul] at h₁
+  rw [bit1_add, bit0_eq_two_mul, ← mul_assoc, ← bit0_eq_two_mul] at h₁ 
   have h₂ := Nat.div_add_mod (bit1 n) (bit0 m)
-  rw [bit1_div_bit0] at h₂
+  rw [bit1_div_bit0] at h₂ 
   exact add_left_cancel (h₂.trans h₁.symm)
 #align nat.bit1_mod_bit0 Nat.bit1_mod_bit0
 -/
@@ -451,14 +451,14 @@ theorem iterate_odd (hf : Involutive f) (hn : Odd n) : f^[n] = f :=
 
 #print Function.Involutive.iterate_eq_self /-
 theorem iterate_eq_self (hf : Involutive f) (hne : f ≠ id) : f^[n] = f ↔ Odd n :=
-  ⟨fun H => odd_iff_not_even.2 fun hn => hne <| by rwa [hf.iterate_even hn, eq_comm] at H,
+  ⟨fun H => odd_iff_not_even.2 fun hn => hne <| by rwa [hf.iterate_even hn, eq_comm] at H ,
     hf.iterate_odd⟩
 #align function.involutive.iterate_eq_self Function.Involutive.iterate_eq_self
 -/
 
 #print Function.Involutive.iterate_eq_id /-
 theorem iterate_eq_id (hf : Involutive f) (hne : f ≠ id) : f^[n] = id ↔ Even n :=
-  ⟨fun H => even_iff_not_odd.2 fun hn => hne <| by rwa [hf.iterate_odd hn] at H, hf.iterate_even⟩
+  ⟨fun H => even_iff_not_odd.2 fun hn => hne <| by rwa [hf.iterate_odd hn] at H , hf.iterate_even⟩
 #align function.involutive.iterate_eq_id Function.Involutive.iterate_eq_id
 -/

bump to nightly-2023-05-28-06

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

ba5d8b97

Diff

@@ -78,12 +78,6 @@ theorem odd_iff_not_even : Odd n ↔ ¬Even n := by rw [not_even_iff, odd_iff]
 #align nat.odd_iff_not_even Nat.odd_iff_not_even
 -/
 
-/- warning: nat.is_compl_even_odd -> Nat.isCompl_even_odd is a dubious translation:
-lean 3 declaration is
-  IsCompl.{0} (Set.{0} Nat) (SemilatticeInf.toPartialOrder.{0} (Set.{0} Nat) (Lattice.toSemilatticeInf.{0} (Set.{0} Nat) (GeneralizedCoheytingAlgebra.toLattice.{0} (Set.{0} Nat) (GeneralizedBooleanAlgebra.toGeneralizedCoheytingAlgebra.{0} (Set.{0} Nat) (BooleanAlgebra.toGeneralizedBooleanAlgebra.{0} (Set.{0} Nat) (Set.booleanAlgebra.{0} Nat)))))) (BooleanAlgebra.toBoundedOrder.{0} (Set.{0} Nat) (Set.booleanAlgebra.{0} Nat)) (setOf.{0} Nat (fun (n : Nat) => Even.{0} Nat Nat.hasAdd n)) (setOf.{0} Nat (fun (n : Nat) => Odd.{0} Nat Nat.semiring n))
-but is expected to have type
-  IsCompl.{0} (Set.{0} Nat) (SemilatticeInf.toPartialOrder.{0} (Set.{0} Nat) (Lattice.toSemilatticeInf.{0} (Set.{0} Nat) (GeneralizedCoheytingAlgebra.toLattice.{0} (Set.{0} Nat) (CoheytingAlgebra.toGeneralizedCoheytingAlgebra.{0} (Set.{0} Nat) (BiheytingAlgebra.toCoheytingAlgebra.{0} (Set.{0} Nat) (BooleanAlgebra.toBiheytingAlgebra.{0} (Set.{0} Nat) (Set.instBooleanAlgebraSet.{0} Nat))))))) (BooleanAlgebra.toBoundedOrder.{0} (Set.{0} Nat) (Set.instBooleanAlgebraSet.{0} Nat)) (setOf.{0} Nat (fun (n : Nat) => Even.{0} Nat instAddNat n)) (setOf.{0} Nat (fun (n : Nat) => Odd.{0} Nat Nat.semiring n))
-Case conversion may be inaccurate. Consider using '#align nat.is_compl_even_odd Nat.isCompl_even_oddₓ'. -/
 theorem isCompl_even_odd : IsCompl { n : ℕ | Even n } { n | Odd n } := by
   simp only [← Set.compl_setOf, isCompl_compl, odd_iff_not_even]
 #align nat.is_compl_even_odd Nat.isCompl_even_odd
@@ -474,12 +468,6 @@ end Function
 
 variable {R : Type _} [Monoid R] [HasDistribNeg R] {n : ℕ}
 
-/- warning: neg_one_pow_eq_one_iff_even -> neg_one_pow_eq_one_iff_even is a dubious translation:
-lean 3 declaration is
-  forall {R : Type.{u1}} [_inst_1 : Monoid.{u1} R] [_inst_2 : HasDistribNeg.{u1} R (MulOneClass.toHasMul.{u1} R (Monoid.toMulOneClass.{u1} R _inst_1))] {n : Nat}, (Ne.{succ u1} R (Neg.neg.{u1} R (InvolutiveNeg.toHasNeg.{u1} R (HasDistribNeg.toHasInvolutiveNeg.{u1} R (MulOneClass.toHasMul.{u1} R (Monoid.toMulOneClass.{u1} R _inst_1)) _inst_2)) (OfNat.ofNat.{u1} R 1 (OfNat.mk.{u1} R 1 (One.one.{u1} R (MulOneClass.toHasOne.{u1} R (Monoid.toMulOneClass.{u1} R _inst_1)))))) (OfNat.ofNat.{u1} R 1 (OfNat.mk.{u1} R 1 (One.one.{u1} R (MulOneClass.toHasOne.{u1} R (Monoid.toMulOneClass.{u1} R _inst_1)))))) -> (Iff (Eq.{succ u1} R (HPow.hPow.{u1, 0, u1} R Nat R (instHPow.{u1, 0} R Nat (Monoid.Pow.{u1} R _inst_1)) (Neg.neg.{u1} R (InvolutiveNeg.toHasNeg.{u1} R (HasDistribNeg.toHasInvolutiveNeg.{u1} R (MulOneClass.toHasMul.{u1} R (Monoid.toMulOneClass.{u1} R _inst_1)) _inst_2)) (OfNat.ofNat.{u1} R 1 (OfNat.mk.{u1} R 1 (One.one.{u1} R (MulOneClass.toHasOne.{u1} R (Monoid.toMulOneClass.{u1} R _inst_1)))))) n) (OfNat.ofNat.{u1} R 1 (OfNat.mk.{u1} R 1 (One.one.{u1} R (MulOneClass.toHasOne.{u1} R (Monoid.toMulOneClass.{u1} R _inst_1)))))) (Even.{0} Nat Nat.hasAdd n))
-but is expected to have type
-  forall {R : Type.{u1}} [_inst_1 : Monoid.{u1} R] [_inst_2 : HasDistribNeg.{u1} R (MulOneClass.toMul.{u1} R (Monoid.toMulOneClass.{u1} R _inst_1))] {n : Nat}, (Ne.{succ u1} R (Neg.neg.{u1} R (InvolutiveNeg.toNeg.{u1} R (HasDistribNeg.toInvolutiveNeg.{u1} R (MulOneClass.toMul.{u1} R (Monoid.toMulOneClass.{u1} R _inst_1)) _inst_2)) (OfNat.ofNat.{u1} R 1 (One.toOfNat1.{u1} R (Monoid.toOne.{u1} R _inst_1)))) (OfNat.ofNat.{u1} R 1 (One.toOfNat1.{u1} R (Monoid.toOne.{u1} R _inst_1)))) -> (Iff (Eq.{succ u1} R (HPow.hPow.{u1, 0, u1} R Nat R (instHPow.{u1, 0} R Nat (Monoid.Pow.{u1} R _inst_1)) (Neg.neg.{u1} R (InvolutiveNeg.toNeg.{u1} R (HasDistribNeg.toInvolutiveNeg.{u1} R (MulOneClass.toMul.{u1} R (Monoid.toMulOneClass.{u1} R _inst_1)) _inst_2)) (OfNat.ofNat.{u1} R 1 (One.toOfNat1.{u1} R (Monoid.toOne.{u1} R _inst_1)))) n) (OfNat.ofNat.{u1} R 1 (One.toOfNat1.{u1} R (Monoid.toOne.{u1} R _inst_1)))) (Even.{0} Nat instAddNat n))
-Case conversion may be inaccurate. Consider using '#align neg_one_pow_eq_one_iff_even neg_one_pow_eq_one_iff_evenₓ'. -/
 theorem neg_one_pow_eq_one_iff_even (h : (-1 : R) ≠ 1) : (-1 : R) ^ n = 1 ↔ Even n :=
   ⟨fun h' => of_not_not fun hn => h <| (Odd.neg_one_pow <| odd_iff_not_even.mpr hn).symm.trans h',
     Even.neg_one_pow⟩

bump to nightly-2023-05-28-04

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

6797a637

Diff

@@ -259,10 +259,8 @@ theorem Odd.of_mul_right (h : Odd (m * n)) : Odd n :=
 /-- If `m` and `n` are natural numbers, then the natural number `m^n` is even
 if and only if `m` is even and `n` is positive. -/
 @[parity_simps]
-theorem even_pow : Even (m ^ n) ↔ Even m ∧ n ≠ 0 :=
-  by
-  induction' n with n ih <;> simp [*, pow_succ', even_mul]
-  tauto
+theorem even_pow : Even (m ^ n) ↔ Even m ∧ n ≠ 0 := by
+  induction' n with n ih <;> simp [*, pow_succ', even_mul]; tauto
 #align nat.even_pow Nat.even_pow
 -/
 
@@ -352,28 +350,20 @@ theorem div_two_mul_two_of_even : Even n → n / 2 * 2 = n := fun h =>
 -/
 
 #print Nat.two_mul_div_two_add_one_of_odd /-
-theorem two_mul_div_two_add_one_of_odd (h : Odd n) : 2 * (n / 2) + 1 = n :=
-  by
-  rw [mul_comm]
-  convert Nat.div_add_mod' n 2
-  rw [odd_iff.mp h]
+theorem two_mul_div_two_add_one_of_odd (h : Odd n) : 2 * (n / 2) + 1 = n := by rw [mul_comm];
+  convert Nat.div_add_mod' n 2; rw [odd_iff.mp h]
 #align nat.two_mul_div_two_add_one_of_odd Nat.two_mul_div_two_add_one_of_odd
 -/
 
 #print Nat.div_two_mul_two_add_one_of_odd /-
-theorem div_two_mul_two_add_one_of_odd (h : Odd n) : n / 2 * 2 + 1 = n :=
-  by
-  convert Nat.div_add_mod' n 2
-  rw [odd_iff.mp h]
+theorem div_two_mul_two_add_one_of_odd (h : Odd n) : n / 2 * 2 + 1 = n := by
+  convert Nat.div_add_mod' n 2; rw [odd_iff.mp h]
 #align nat.div_two_mul_two_add_one_of_odd Nat.div_two_mul_two_add_one_of_odd
 -/
 
 #print Nat.one_add_div_two_mul_two_of_odd /-
-theorem one_add_div_two_mul_two_of_odd (h : Odd n) : 1 + n / 2 * 2 = n :=
-  by
-  rw [add_comm]
-  convert Nat.div_add_mod' n 2
-  rw [odd_iff.mp h]
+theorem one_add_div_two_mul_two_of_odd (h : Odd n) : 1 + n / 2 * 2 = n := by rw [add_comm];
+  convert Nat.div_add_mod' n 2; rw [odd_iff.mp h]
 #align nat.one_add_div_two_mul_two_of_odd Nat.one_add_div_two_mul_two_of_odd
 -/

bump to nightly-2023-02-21-16

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

1107b979

Changes in mathlib4

mathlib3

mathlib4

chore: reformat deprecation warnings on one line, if possible (#12335)

Occasionally, remove a "deprecated by" or "deprecated since", to fit the line length.

This is desirable (to me) because

it's more compact: I don't see a good reason for these declarations taking up more space than needed; as I understand it, deprecated lemmas are not supposed to be used in mathlib anyway
putting the date on the same line as the attribute makes it easier to discover un-dated deprecations; they also ease writing a tool to replace these by a machine-readable version using leanprover/lean4#3968

45346d9f

Diff

@@ -230,8 +230,7 @@ theorem even_mul_pred_self : ∀ n : ℕ, Even (n * (n - 1))
   | (n + 1) => mul_comm (n + 1 - 1) (n + 1) ▸ even_mul_succ_self n
 #align nat.even_mul_self_pred Nat.even_mul_pred_self
 
-@[deprecated] -- 2024-01-20
-alias even_mul_self_pred := even_mul_pred_self
+@[deprecated] alias even_mul_self_pred := even_mul_pred_self -- 2024-01-20
 
 theorem two_mul_div_two_of_even : Even n → 2 * (n / 2) = n := fun h =>
   Nat.mul_div_cancel_left' (even_iff_two_dvd.mp h)

chore: split Subsingleton,Nontrivial off of Data.Set.Basic (#11832)

Moves definition of and lemmas related to Set.Subsingleton and Set.Nontrivial to a new file, so that Basic can be shorter.

493a947e

Diff

@@ -6,7 +6,7 @@ Authors: Jeremy Avigad, Benjamin Davidson
 import Mathlib.Algebra.Parity
 import Mathlib.Data.Nat.Bits
 import Mathlib.Data.Nat.ModEq
-import Mathlib.Data.Set.Basic
+import Mathlib.Data.Set.Subsingleton
 
 #align_import data.nat.parity from "leanprover-community/mathlib"@"48fb5b5280e7c81672afc9524185ae994553ebf4"

chore(Data/Nat/Defs): Integrate Nat.sqrt material (#11866)

Move the content of Data.Nat.ForSqrt and Data.Nat.Sqrt to Data.Nat.Defs by using Nat-specific Std lemmas rather than the mathlib general ones. This makes it ready to move to Std if wanted.

d4b9a267

Diff

@@ -42,6 +42,11 @@ theorem even_iff : Even n ↔ n % 2 = 0 :=
 
 instance : DecidablePred (Even : ℕ → Prop) := fun _ => decidable_of_iff _ even_iff.symm
 
+/-- `IsSquare` can be decided on `ℕ` by checking against the square root. -/
+instance : DecidablePred (IsSquare : ℕ → Prop) :=
+  fun m ↦ decidable_of_iff' (Nat.sqrt m * Nat.sqrt m = m) <| by
+    simp_rw [← Nat.exists_mul_self m, IsSquare, eq_comm]
+
 theorem odd_iff : Odd n ↔ n % 2 = 1 :=
   ⟨fun ⟨m, hm⟩ => by norm_num [hm, add_mod],
     fun h => ⟨n / 2, (mod_add_div n 2).symm.trans (by rw [h, add_comm])⟩⟩

feat: A natural is odd iff it's coprime with 2 (#10222)

From LeanAPAP

66ad5718

Diff

@@ -156,6 +156,8 @@ theorem Odd.sub_odd (hm : Odd m) (hn : Odd n) : Even (m - n) :=
     simp only [tsub_eq_zero_iff_le.mpr h, even_zero]
 #align nat.odd.sub_odd Nat.Odd.sub_odd
 
+alias _root_.Odd.tsub_odd := Nat.Odd.sub_odd
+
 @[parity_simps]
 theorem even_mul : Even (m * n) ↔ Even m ∨ Even n := by
   cases' mod_two_eq_zero_or_one m with h₁ h₁ <;> cases' mod_two_eq_zero_or_one n with h₂ h₂ <;>

chore(*): shake imports (#10199)

Remove Data.Set.Basic from scripts/noshake.json.
Remove an exception that was used by examples only, move these examples to a new test file.
Drop an exception for Order.Filter.Basic dependency on Control.Traversable.Instances, as the relevant parts were moved to Order.Filter.ListTraverse.
Run lake exe shake --fix.

c167d468

Diff

@@ -6,6 +6,7 @@ Authors: Jeremy Avigad, Benjamin Davidson
 import Mathlib.Algebra.Parity
 import Mathlib.Data.Nat.Bits
 import Mathlib.Data.Nat.ModEq
+import Mathlib.Data.Set.Basic
 
 #align_import data.nat.parity from "leanprover-community/mathlib"@"48fb5b5280e7c81672afc9524185ae994553ebf4"

feat(Parity): add lemmas about x ^ n = ±y ^ n (#9881)

7e1799b7

Diff

@@ -339,13 +339,44 @@ end Involutive
 
 end Function
 
-variable {R : Type*} [Monoid R] [HasDistribNeg R] {n : ℕ}
-
-theorem neg_one_pow_eq_one_iff_even (h : (-1 : R) ≠ 1) : (-1 : R) ^ n = 1 ↔ Even n :=
+theorem neg_one_pow_eq_one_iff_even {R : Type*} [Monoid R] [HasDistribNeg R] {n : ℕ}
+    (h : (-1 : R) ≠ 1) : (-1 : R) ^ n = 1 ↔ Even n :=
   ⟨fun h' => of_not_not fun hn => h <| (Odd.neg_one_pow <| odd_iff_not_even.mpr hn).symm.trans h',
     Even.neg_one_pow⟩
 #align neg_one_pow_eq_one_iff_even neg_one_pow_eq_one_iff_even
 
+section LinearOrderedRing
+
+variable {R : Type*} [LinearOrderedRing R] {a b : R} {n : ℕ}
+
+theorem pow_eq_pow_iff_of_ne_zero (hn : n ≠ 0) : a ^ n = b ^ n ↔ a = b ∨ a = -b ∧ Even n :=
+  match n.even_xor_odd with
+  | .inl hne => by simp only [*, and_true, ← abs_eq_abs,
+    ← pow_left_inj (abs_nonneg a) (abs_nonneg b) hn, hne.1.pow_abs]
+  | .inr hn => by simp [hn, (hn.1.strictMono_pow (R := R)).injective.eq_iff]
+
+theorem pow_eq_pow_iff_cases : a ^ n = b ^ n ↔ n = 0 ∨ a = b ∨ a = -b ∧ Even n := by
+  rcases eq_or_ne n 0 with rfl | hn <;> simp [pow_eq_pow_iff_of_ne_zero, *]
+
+theorem pow_eq_one_iff_of_ne_zero (hn : n ≠ 0) : a ^ n = 1 ↔ a = 1 ∨ a = -1 ∧ Even n := by
+  simp [← pow_eq_pow_iff_of_ne_zero hn]
+
+theorem pow_eq_one_iff_cases : a ^ n = 1 ↔ n = 0 ∨ a = 1 ∨ a = -1 ∧ Even n := by
+  simp [← pow_eq_pow_iff_cases]
+
+theorem pow_eq_neg_pow_iff (hb : b ≠ 0) : a ^ n = -b ^ n ↔ a = -b ∧ Odd n :=
+  match n.even_or_odd with
+  | .inl he =>
+    suffices a ^ n > -b ^ n by simpa [he] using this.ne'
+    lt_of_lt_of_le (by simp [he.pow_pos hb]) (he.pow_nonneg _)
+  | .inr ho => by
+    simp only [ho, and_true, ← ho.neg_pow, (ho.strictMono_pow (R := R)).injective.eq_iff]
+
+theorem pow_eq_neg_one_iff : a ^ n = -1 ↔ a = -1 ∧ Odd n := by
+  simpa using pow_eq_neg_pow_iff (R := R) one_ne_zero
+
+end LinearOrderedRing
+
 /-- If `a` is even, then `n` is odd iff `n % a` is odd. -/
 theorem Odd.mod_even_iff {n a : ℕ} (ha : Even a) : Odd (n % a) ↔ Odd n :=
   ((even_sub' <| mod_le n a).mp <|

feat: Int.{even_sub_one,even_mul_pred_self} (#9859)

Also rename Nat.even_mul_self_pred for consistency with Nat.even_mul_succ_self.

0500719e

Diff

@@ -217,10 +217,13 @@ theorem even_mul_succ_self (n : ℕ) : Even (n * (n + 1)) := by
   exact em _
 #align nat.even_mul_succ_self Nat.even_mul_succ_self
 
-theorem even_mul_self_pred : ∀ n : ℕ, Even (n * (n - 1))
+theorem even_mul_pred_self : ∀ n : ℕ, Even (n * (n - 1))
   | 0 => even_zero
   | (n + 1) => mul_comm (n + 1 - 1) (n + 1) ▸ even_mul_succ_self n
-#align nat.even_mul_self_pred Nat.even_mul_self_pred
+#align nat.even_mul_self_pred Nat.even_mul_pred_self
+
+@[deprecated] -- 2024-01-20
+alias even_mul_self_pred := even_mul_pred_self
 
 theorem two_mul_div_two_of_even : Even n → 2 * (n / 2) = n := fun h =>
   Nat.mul_div_cancel_left' (even_iff_two_dvd.mp h)

chore(Function): rename some lemmas (#9738)

Merge Function.left_id and Function.comp.left_id into Function.id_comp.
Merge Function.right_id and Function.comp.right_id into Function.comp_id.
Merge Function.comp_const_right and Function.comp_const into Function.comp_const, use explicit arguments.
Move Function.const_comp to Mathlib.Init.Function, use explicit arguments.

87c10369

Diff

@@ -305,7 +305,7 @@ theorem iterate_bit0 (hf : Involutive f) (n : ℕ) : f^[bit0 n] = id := by
 #align function.involutive.iterate_bit0 Function.Involutive.iterate_bit0
 
 theorem iterate_bit1 (hf : Involutive f) (n : ℕ) : f^[bit1 n] = f := by
-  rw [bit1, ← succ_eq_add_one, iterate_succ, hf.iterate_bit0, comp.left_id]
+  rw [bit1, ← succ_eq_add_one, iterate_succ, hf.iterate_bit0, id_comp]
 #align function.involutive.iterate_bit1 Function.Involutive.iterate_bit1
 
 end
@@ -320,7 +320,7 @@ theorem iterate_even (hf : Involutive f) (hn : Even n) : f^[n] = id := by
 
 theorem iterate_odd (hf : Involutive f) (hn : Odd n) : f^[n] = f := by
   rcases hn with ⟨m, rfl⟩
-  rw [iterate_add, hf.iterate_two_mul, comp.left_id, iterate_one]
+  rw [iterate_add, hf.iterate_two_mul, id_comp, iterate_one]
 #align function.involutive.iterate_odd Function.Involutive.iterate_odd
 
 theorem iterate_eq_self (hf : Involutive f) (hne : f ≠ id) : f^[n] = f ↔ Odd n :=

refactor: Split off basic Nat file (#9551)

Data.Nat.Basic is currently made of two things:

Basic lemmas that continue the theory in Std (and could belong there, really)
Basic algebraic order instances

I need the first ones earlier in the algebraic order hierarchy, hence the split.

Part of #9411. Similar to #9443

497ed074

Diff

@@ -3,8 +3,9 @@ Copyright (c) 2019 Jeremy Avigad. All rights reserved.
 Released under Apache 2.0 license as described in the file LICENSE.
 Authors: Jeremy Avigad, Benjamin Davidson
 -/
-import Mathlib.Data.Nat.ModEq
 import Mathlib.Algebra.Parity
+import Mathlib.Data.Nat.Bits
+import Mathlib.Data.Nat.ModEq
 
 #align_import data.nat.parity from "leanprover-community/mathlib"@"48fb5b5280e7c81672afc9524185ae994553ebf4"

chore: minimize some imports (#9559)

Started from Algebra/Periodic.lean with some snowball sampling. Seems to be somewhat disjoint from the tree shaking in #9347.

bb7a43e4

Diff

@@ -4,7 +4,6 @@ Released under Apache 2.0 license as described in the file LICENSE.
 Authors: Jeremy Avigad, Benjamin Davidson
 -/
 import Mathlib.Data.Nat.ModEq
-import Mathlib.Data.Nat.Prime
 import Mathlib.Algebra.Parity
 
 #align_import data.nat.parity from "leanprover-community/mathlib"@"48fb5b5280e7c81672afc9524185ae994553ebf4"

chore: space after ← (#8178)

Co-authored-by: Moritz Firsching <firsching@google.com>

5fb9beab

Diff

@@ -305,7 +305,7 @@ theorem iterate_bit0 (hf : Involutive f) (n : ℕ) : f^[bit0 n] = id := by
 #align function.involutive.iterate_bit0 Function.Involutive.iterate_bit0
 
 theorem iterate_bit1 (hf : Involutive f) (n : ℕ) : f^[bit1 n] = f := by
-  rw [bit1, ←succ_eq_add_one, iterate_succ, hf.iterate_bit0, comp.left_id]
+  rw [bit1, ← succ_eq_add_one, iterate_succ, hf.iterate_bit0, comp.left_id]
 #align function.involutive.iterate_bit1 Function.Involutive.iterate_bit1
 
 end

chore: bump to v4.3.0-rc2 (#8366)

PR contents

This is the supremum of

#8284
#8056
#8023
#8332
#8226 (already approved)
#7834 (already approved)

along with some minor fixes from failures on nightly-testing as Mathlib master is merged into it.

Note that some PRs for changes that are already compatible with the current toolchain and will be necessary have already been split out: #8380.

I am hopeful that in future we will be able to progressively merge adaptation PRs into a bump/v4.X.0 branch, so we never end up with a "big merge" like this. However one of these adaptation PRs (#8056) predates my new scheme for combined CI, and it wasn't possible to keep that PR viable in the meantime.

Lean PRs involved in this bump

In particular this includes adjustments for the Lean PRs

leanprover/lean4#2778

We can get rid of all the

local macro_rules | `($x ^ $y) => `(HPow.hPow $x $y) -- Porting note: See issue [lean4#2220](https://github.com/leanprover/lean4/pull/2220)

macros across Mathlib (and in any projects that want to write natural number powers of reals).

leanprover/lean4#2722

Changes the default behaviour of simp to (config := {decide := false}). This makes simp (and consequentially norm_num) less powerful, but also more consistent, and less likely to blow up in long failures. This requires a variety of changes: changing some previously by simp or norm_num to decide or rfl, or adding (config := {decide := true}).

leanprover/lean4#2783

This changed the behaviour of simp so that simp [f] will only unfold "fully applied" occurrences of f. The old behaviour can be recovered with simp (config := { unfoldPartialApp := true }). We may in future add a syntax for this, e.g. simp [!f]; please provide feedback! In the meantime, we have made the following changes:

switching to using explicit lemmas that have the intended level of application
(config := { unfoldPartialApp := true }) in some places, to recover the old behaviour
Using @[eqns] to manually adjust the equation lemmas for a particular definition, recovering the old behaviour just for that definition. See #8371, where we do this for Function.comp and Function.flip.

This change in Lean may require further changes down the line (e.g. adding the !f syntax, and/or upstreaming the special treatment for Function.comp and Function.flip, and/or removing this special treatment). Please keep an open and skeptical mind about these changes!

Co-authored-by: leanprover-community-mathlib4-bot <leanprover-community-mathlib4-bot@users.noreply.github.com> Co-authored-by: Scott Morrison <scott.morrison@gmail.com> Co-authored-by: Eric Wieser <wieser.eric@gmail.com> Co-authored-by: Mauricio Collares <mauricio@collares.org>

40b64f79

Diff

@@ -284,9 +284,8 @@ end
 example (m n : ℕ) (h : Even m) : ¬Even (n + 3) ↔ Even (m ^ 2 + m + n) := by
   simp [*, two_ne_zero, parity_simps]
 
-/- Porting note: the `simp` lemmas about `bit*` no longer apply, but `simp` in Lean 4 currently
-simplifies decidable propositions. This may change in the future. -/
-example : ¬Even 25394535 := by simp only
+/- Porting note: the `simp` lemmas about `bit*` no longer apply. -/
+example : ¬Even 25394535 := by decide
 
 end Nat

feat: add 2-coloring of pathGraph and prove its chromatic number is 2 (#8166)

Define a bicoloring for pathGraph and prove that when 2 ≤ n its chromatic number is 2. Creates a ConcreteColorings module to hold such colorings of concrete graphs.

e004ac1c

Diff

@@ -122,6 +122,12 @@ theorem even_add' : Even (m + n) ↔ (Odd m ↔ Odd n) := by
 theorem even_add_one : Even (n + 1) ↔ ¬Even n := by simp [even_add]
 #align nat.even_add_one Nat.even_add_one
 
+theorem succ_mod_two_eq_zero_iff {m : ℕ} : (m + 1) % 2 = 0 ↔ m % 2 = 1 := by
+  simp [← Nat.even_iff, ← Nat.not_even_iff, parity_simps]
+
+theorem succ_mod_two_eq_one_iff {m : ℕ} : (m + 1) % 2 = 1 ↔ m % 2 = 0 := by
+  simp [← Nat.even_iff, ← Nat.not_even_iff, parity_simps]
+
 set_option linter.deprecated false in
 @[simp]
 theorem not_even_bit1 (n : ℕ) : ¬Even (bit1 n) := by simp [bit1, parity_simps]

feat: fix norm num with arguments (#6600)

norm_num was passing the wrong syntax node to elabSimpArgs when elaborating, which essentially had the effect of ignoring all arguments it was passed, i.e. norm_num [add_comm] would not try to commute addition in the simp step. The fix itself is very simple (though not obvious to debug!), probably using TSyntax more would help avoid such issues in future.

Due to this bug many norm_num [blah] became rw [blah]; norm_num or similar, sometimes with porting notes, sometimes not, we fix these porting notes and other regressions during the port also.

Interestingly cancel_denoms uses norm_num [<- mul_assoc] internally, so cancel_denoms also got stronger with this change.

49a849ef

Diff

@@ -42,7 +42,7 @@ theorem even_iff : Even n ↔ n % 2 = 0 :=
 instance : DecidablePred (Even : ℕ → Prop) := fun _ => decidable_of_iff _ even_iff.symm
 
 theorem odd_iff : Odd n ↔ n % 2 = 1 :=
-  ⟨fun ⟨m, hm⟩ => by rw [hm, add_mod, mul_mod_right]; rfl,
+  ⟨fun ⟨m, hm⟩ => by norm_num [hm, add_mod],
     fun h => ⟨n / 2, (mod_add_div n 2).symm.trans (by rw [h, add_comm])⟩⟩
 #align nat.odd_iff Nat.odd_iff

chore: banish Type _ and Sort _ (#6499)

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

This has nice performance benefits.

32de3f67

Diff

@@ -290,7 +290,7 @@ namespace Function
 
 namespace Involutive
 
-variable {α : Type _} {f : α → α} {n : ℕ}
+variable {α : Type*} {f : α → α} {n : ℕ}
 
 set_option linter.deprecated false in
 section
@@ -331,7 +331,7 @@ end Involutive
 
 end Function
 
-variable {R : Type _} [Monoid R] [HasDistribNeg R] {n : ℕ}
+variable {R : Type*} [Monoid R] [HasDistribNeg R] {n : ℕ}
 
 theorem neg_one_pow_eq_one_iff_even (h : (-1 : R) ≠ 1) : (-1 : R) ^ n = 1 ↔ Even n :=
   ⟨fun h' => of_not_not fun hn => h <| (Odd.neg_one_pow <| odd_iff_not_even.mpr hn).symm.trans h',

chore: script to replace headers with #align_import statements (#5979)

depends on: #5966

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

89aa3a3b

Diff

@@ -2,16 +2,13 @@
 Copyright (c) 2019 Jeremy Avigad. All rights reserved.
 Released under Apache 2.0 license as described in the file LICENSE.
 Authors: Jeremy Avigad, Benjamin Davidson
-
-! This file was ported from Lean 3 source module data.nat.parity
-! leanprover-community/mathlib commit 48fb5b5280e7c81672afc9524185ae994553ebf4
-! Please do not edit these lines, except to modify the commit id
-! if you have ported upstream changes.
 -/
 import Mathlib.Data.Nat.ModEq
 import Mathlib.Data.Nat.Prime
 import Mathlib.Algebra.Parity
 
+#align_import data.nat.parity from "leanprover-community/mathlib"@"48fb5b5280e7c81672afc9524185ae994553ebf4"
+
 /-!
 # Parity of natural numbers

refactor: move all register_simp_attrs to 1 file (#5681)

There are slight differences between mathlib3 and mathlib4 (different set of attributes, different lemmas are in core/std), so I redid the same refactor instead of forward-porting changes.

mathlib3 PR: leanprover-community/mathlib#19223

ceaa4ecb

Diff

@@ -4,7 +4,7 @@ Released under Apache 2.0 license as described in the file LICENSE.
 Authors: Jeremy Avigad, Benjamin Davidson
 
 ! This file was ported from Lean 3 source module data.nat.parity
-! leanprover-community/mathlib commit 8631e2d5ea77f6c13054d9151d82b83069680cb1
+! leanprover-community/mathlib commit 48fb5b5280e7c81672afc9524185ae994553ebf4
 ! Please do not edit these lines, except to modify the commit id
 ! if you have ported upstream changes.
 -/

feat: port NumberTheory.SumFourSquares (#4604)

eb95d896

Diff

@@ -64,6 +64,9 @@ theorem even_iff_not_odd : Even n ↔ ¬Odd n := by rw [not_odd_iff, even_iff]
 theorem odd_iff_not_even : Odd n ↔ ¬Even n := by rw [not_even_iff, odd_iff]
 #align nat.odd_iff_not_even Nat.odd_iff_not_even
 
+theorem _root_.Odd.not_two_dvd_nat (h : Odd n) : ¬(2 ∣ n) := by
+  rwa [← even_iff_two_dvd, ← odd_iff_not_even]
+
 theorem isCompl_even_odd : IsCompl { n : ℕ | Even n } { n | Odd n } := by
   simp only [← Set.compl_setOf, isCompl_compl, odd_iff_not_even]
 #align nat.is_compl_even_odd Nat.isCompl_even_odd

chore: bye-bye, solo bys! (#3825)

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".

14167e48

Diff

@@ -263,8 +263,7 @@ theorem bit0_mod_bit0 : bit0 n % bit0 m = bit0 (n % m) := by
 #align nat.bit0_mod_bit0 Nat.bit0_mod_bit0
 
 @[simp]
-theorem bit1_mod_bit0 : bit1 n % bit0 m = bit1 (n % m) :=
-  by
+theorem bit1_mod_bit0 : bit1 n % bit0 m = bit1 (n % m) := by
   have h₁ := congr_arg bit1 (Nat.div_add_mod n m)
   -- `∀ m n : ℕ, bit0 m * n = bit0 (m * n)` seems to be missing...
   rw [bit1_add, bit0_eq_two_mul, ← mul_assoc, ← bit0_eq_two_mul] at h₁

chore: fix #align lines (#3640)

This PR fixes two things:

Most align statements for definitions and theorems and instances that are separated by two newlines from the relevant declaration (s/\n\n#align/\n#align). This is often seen in the mathport output after ending calc blocks.
All remaining more-than-one-line #align statements. (This was needed for a script I wrote for #3630.)

2b42dc7c

Diff

@@ -317,7 +317,6 @@ theorem iterate_even (hf : Involutive f) (hn : Even n) : f^[n] = id := by
 theorem iterate_odd (hf : Involutive f) (hn : Odd n) : f^[n] = f := by
   rcases hn with ⟨m, rfl⟩
   rw [iterate_add, hf.iterate_two_mul, comp.left_id, iterate_one]
-
 #align function.involutive.iterate_odd Function.Involutive.iterate_odd
 
 theorem iterate_eq_self (hf : Involutive f) (hne : f ≠ id) : f^[n] = f ↔ Odd n :=

feat: port GroupTheory.Index (#2222)

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

94fc5b20

Diff

@@ -73,7 +73,7 @@ theorem even_xor_odd (n : ℕ) : Xor' (Even n) (Odd n) := by
 #align nat.even_xor_odd Nat.even_xor_odd
 
 theorem even_or_odd (n : ℕ) : Even n ∨ Odd n :=
-  xor.or (even_xor_odd n)
+  (even_xor_odd n).or
 #align nat.even_or_odd Nat.even_or_odd
 
 theorem even_or_odd' (n : ℕ) : ∃ k, n = 2 * k ∨ n = 2 * k + 1 := by