wiedijk_100_theorems.inverse_triangle_sum

Changes since the initial port

The following section lists changes to this file in mathlib3 and mathlib4 that occured after the initial port. Most recent changes are shown first. Hovering over a commit will show all commits associated with the same mathlib3 commit.

Changes in mathlib3

5563b1b4

(last sync)

Changes in mathlib3port

mathlib3

mathlib3port

08b081ea

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) 2020. All rights reserved.
 Released under Apache 2.0 license as described in the file LICENSE.
 Authors: Jalex Stark, Yury Kudryashov
 -/
-import Mathbin.Algebra.BigOperators.Basic
-import Mathbin.Data.Real.Basic
+import Algebra.BigOperators.Basic
+import Data.Real.Basic
 
 #align_import wiedijk_100_theorems.inverse_triangle_sum from "leanprover-community/mathlib"@"08b081ea92d80e3a41f899eea36ef6d56e0f1db0"

08b081ea

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) 2020. All rights reserved.
 Released under Apache 2.0 license as described in the file LICENSE.
 Authors: Jalex Stark, Yury Kudryashov
-
-! This file was ported from Lean 3 source module wiedijk_100_theorems.inverse_triangle_sum
-! leanprover-community/mathlib commit 08b081ea92d80e3a41f899eea36ef6d56e0f1db0
-! Please do not edit these lines, except to modify the commit id
-! if you have ported upstream changes.
 -/
 import Mathbin.Algebra.BigOperators.Basic
 import Mathbin.Data.Real.Basic
 
+#align_import wiedijk_100_theorems.inverse_triangle_sum from "leanprover-community/mathlib"@"08b081ea92d80e3a41f899eea36ef6d56e0f1db0"
+
 /-!
 # Sum of the Reciprocals of the Triangular Numbers

08b081ea

bump to nightly-2023-07-17-03

mathlib commit https://github.com/leanprover-community/mathlib/commit/bf2428c9486c407ca38b5b3fb10b87dad0bc99fa

a159b65f

Diff

@@ -4,7 +4,7 @@ Released under Apache 2.0 license as described in the file LICENSE.
 Authors: Jalex Stark, Yury Kudryashov
 
 ! This file was ported from Lean 3 source module wiedijk_100_theorems.inverse_triangle_sum
-! leanprover-community/mathlib commit 5563b1b49e86e135e8c7b556da5ad2f5ff881cad
+! leanprover-community/mathlib commit 08b081ea92d80e3a41f899eea36ef6d56e0f1db0
 ! Please do not edit these lines, except to modify the commit id
 ! if you have ported upstream changes.
 -/
@@ -14,6 +14,9 @@ import Mathbin.Data.Real.Basic
 /-!
 # Sum of the Reciprocals of the Triangular Numbers
 
+> THIS FILE IS SYNCHRONIZED WITH MATHLIB4.
+> Any changes to this file require a corresponding PR to mathlib4.
+
 This file proves Theorem 42 from the [100 Theorems List](https://www.cs.ru.nl/~freek/100/).
 
 We interpret “triangular numbers” as naturals of the form $\frac{k(k+1)}{2}$ for natural `k`.

5563b1b4

bump to nightly-2023-06-17-03

mathlib commit https://github.com/leanprover-community/mathlib/commit/893964fc28cefbcffc7cb784ed00a2895b4e65cf

253178d1

Diff

@@ -3,8 +3,8 @@ Copyright (c) 2020. All rights reserved.
 Released under Apache 2.0 license as described in the file LICENSE.
 Authors: Jalex Stark, Yury Kudryashov
 
-! This file was ported from Lean 3 source module «100-theorems-list».«42_inverse_triangle_sum»
-! leanprover-community/mathlib commit 328375597f2c0dd00522d9c2e5a33b6a6128feeb
+! This file was ported from Lean 3 source module wiedijk_100_theorems.inverse_triangle_sum
+! leanprover-community/mathlib commit 5563b1b49e86e135e8c7b556da5ad2f5ff881cad
 ! Please do not edit these lines, except to modify the commit id
 ! if you have ported upstream changes.
 -/

Changes in mathlib4

mathlib3

mathlib4

5563b1b4

chore: adaptations to lean 4.8.0 (#12549)

e50e1c94

Diff

@@ -33,7 +33,7 @@ theorem Theorems100.inverse_triangle_sum :
   refine' sum_range_induction _ _ (if_pos rfl) _
   rintro (_ | n)
   · rw [if_neg, if_pos] <;> norm_num
-  simp_rw [if_neg (Nat.succ_ne_zero _), Nat.succ_eq_add_one]
+  simp only [Nat.succ_ne_zero, ↓reduceIte, Nat.cast_succ]
   have A : (n + 1 + 1 : ℚ) ≠ 0 := by norm_cast; norm_num
   push_cast
   field_simp

5563b1b4

chore: make List.mem_split an alias of List.append_of_mem (#11060)

List.mem_split duplicates List.append_of_mem from Std: https://github.com/leanprover/std4/blob/a756b7d643ae5dcd7bf314e99f8e493e5d81b9ed/Std/Data/List/Lemmas.lean#L94-L96

This PR makes it an alias.

Co-authored-by: Yaël Dillies <yael.dillies@gmail.com>

9682f6b2

Diff

@@ -28,7 +28,7 @@ open scoped BigOperators
 open Finset
 
 /-- **Sum of the Reciprocals of the Triangular Numbers** -/
-theorem Theorem100.inverse_triangle_sum :
+theorem Theorems100.inverse_triangle_sum :
     ∀ n, ∑ k in range n, (2 : ℚ) / (k * (k + 1)) = if n = 0 then 0 else 2 - (2 : ℚ) / n := by
   refine' sum_range_induction _ _ (if_pos rfl) _
   rintro (_ | n)
@@ -38,4 +38,4 @@ theorem Theorem100.inverse_triangle_sum :
   push_cast
   field_simp
   ring
-#align theorem_100.inverse_triangle_sum Theorem100.inverse_triangle_sum
+#align theorem_100.inverse_triangle_sum Theorems100.inverse_triangle_sum

5563b1b4

chore: split Data.Real.Basic (#8356)

Co-authored-by: Scott Morrison <scott.morrison@gmail.com>

43e32656

Diff

@@ -5,6 +5,7 @@ Authors: Jalex Stark, Yury Kudryashov
 -/
 import Mathlib.Algebra.BigOperators.Basic
 import Mathlib.Data.Real.Basic
+import Mathlib.Tactic.FieldSimp
 
 #align_import wiedijk_100_theorems.inverse_triangle_sum from "leanprover-community/mathlib"@"5563b1b49e86e135e8c7b556da5ad2f5ff881cad"

5563b1b4

field_simp: Use positivity as a discharger (#6312)

The main reasons is that having h : 0 < denom in the context should suffice for field_simp to do its job, without the need to manually pass h.ne or similar.

Quite a few have := … ≠ 0 could be dropped, and some field_simp calls no longer need explicit arguments; this is promising.

This does break some proofs where field_simp was not used as a closing tactic, and it now shuffles terms around a bit different. These were fixed. Using field_simp in the middle of a proof seems rather fragile anyways.

As a drive-by contribution, positivity now knows about π > 0.

fixes: #4835

Co-authored-by: Matthew Ballard <matt@mrb.email>

6b391efa

Diff

@@ -35,6 +35,6 @@ theorem Theorem100.inverse_triangle_sum :
   simp_rw [if_neg (Nat.succ_ne_zero _), Nat.succ_eq_add_one]
   have A : (n + 1 + 1 : ℚ) ≠ 0 := by norm_cast; norm_num
   push_cast
-  field_simp [Nat.cast_add_one_ne_zero]
+  field_simp
   ring
 #align theorem_100.inverse_triangle_sum Theorem100.inverse_triangle_sum

5563b1b4

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

@@ -2,15 +2,12 @@
 Copyright (c) 2020. All rights reserved.
 Released under Apache 2.0 license as described in the file LICENSE.
 Authors: Jalex Stark, Yury Kudryashov
-
-! This file was ported from Lean 3 source module wiedijk_100_theorems.inverse_triangle_sum
-! leanprover-community/mathlib commit 5563b1b49e86e135e8c7b556da5ad2f5ff881cad
-! Please do not edit these lines, except to modify the commit id
-! if you have ported upstream changes.
 -/
 import Mathlib.Algebra.BigOperators.Basic
 import Mathlib.Data.Real.Basic
 
+#align_import wiedijk_100_theorems.inverse_triangle_sum from "leanprover-community/mathlib"@"5563b1b49e86e135e8c7b556da5ad2f5ff881cad"
+
 /-!
 # Sum of the Reciprocals of the Triangular Numbers

5563b1b4

feat: port MeasureTheory.Function.ConditionalExpectation.CondexpL1 (#5174)

dd445718

`wiedijk_100_theorems.inverse_triangle_sum` ⟷ `Archive.Wiedijk100Theorems.InverseTriangleSum`

Changes since the initial port

Changes in mathlib3

Changes in mathlib3port

Changes in mathlib4

Dependencies 3 + 255

wiedijk_100_theorems.inverse_triangle_sum ⟷ Archive.Wiedijk100Theorems.InverseTriangleSum

Changes since the initial port

Changes in mathlib3

Changes in mathlib3port

Changes in mathlib4

Dependencies 3 + 255

`wiedijk_100_theorems.inverse_triangle_sum` ⟷ `Archive.Wiedijk100Theorems.InverseTriangleSum`