awhecmu/canonical-drafter-extract-mathlib huggingface dataset:
-- Lean 4 proof step from Mathlib.CategoryTheory.Abelian.DiagramLemmas.Four (goal)
Goal:
C : Type u_1
inst : Category.{v_1, u_1} C
inst_1 : Abelian.{v_1, u_1} C
R₁ R₂ : ComposableArrows.{v_1, u_1} C 3
φ : R₁ ⟶ R₂
hR₁ : R₁.map' 0 2 mono_of_epi_of_mono_of_mono'._proof_2 mono_of_epi_of_mono_of_mono'._proof_4 = 0
hR₁' :
  (mk₂ (R₁.map' 1 2 mono_of_epi_of_mono_of_mono'._proof_6 mono_of_epi_of_mono_of_mono'._proof_4)
      (R₁.map' 2 3 mono_of_epi_of_mono_of_mono'._proof_4 mono_of_epi_of_mono_of_mono'._proof_7)).Exact
hR₂ :
  (mk₂ (R₂.map' 0 1 mono_of_epi_of_mono_of_mono'._proof_9 mono_of_epi_of_mono_of_mono'._proof_11)
      (R₂.map' 1 2 mono_of_epi_of_mono_of_mono'._proof_6 mono_of_epi_of_mono_of_mono'._proof_4)).Exact
h₀ : Epi (app' φ 0 mono_of_epi_of_mono_of_mono'._proof_13)
h₁_1 : Mono (app' φ 1 mono_of_epi_of_mono_of_mono'._proof_11)
h₃ : Mono (app' φ 3 mono_of_epi_of_mono_of_mono'._proof_7)
A : C
f₂ : A ⟶ R₁.obj' 2 mono_of_epi_of_mono_of_mono'._proof_4
h₁ : f₂ ≫ app' φ 2 mono_of_epi_of_mono_of_mono'._proof_4 = 0
h₂ : f₂ ≫ R₁.map' 2 3 ⋯ ⋯ = 0
A₁ : C
π₁ : A₁ ⟶ A
w : Epi π₁
f₁ :
  A₁ ⟶
    ((mk₂ (R₁.map' 1 2 mono_of_epi_of_mono_of_mono'._proof_6 mono_of_epi_of_mono_of_mono'._proof_4)
            (R₁.map' 2 3 mono_of_epi_of_mono_of_mono'._proof_4 mono_of_epi_of_mono_of_mono'._proof_7)).sc
        ⋯ 0 ⋯).X₁
hf₁ : π₁ ≫ f₂ = f₁ ≫ R₁.map (homOfLE ⋯)
rw :
  Eq (α := A₁ ⟶ R₂.obj ⟨2, ⋯⟩)
    (f₁ ≫ CategoryStruct.comp (Y := R₂.obj' 1 ⋯) (app' φ 1 ⋯) (R₂.map' 1 2 ⋯ ⋯) : A₁ ⟶ R₂.obj ⟨2, ⋯⟩)
    (0 : A₁ ⟶ R₂.obj ⟨2, ⋯⟩)
rw₁ :
  Eq (α := A₁ ⟶ R₂.obj ⟨2, ⋯⟩)
    (f₁ ≫
        CategoryStruct.comp (Y := R₁.obj ⟨2, ⋯⟩)
          (R₁.map (homOfLE ⋯) : R₁.obj (⟨1, ⋯⟩ : Fin (HAdd.hAdd (α := ℕ) 3 1)) ⟶ R₁.obj ⟨2, ⋯⟩)
          (φ.app ⟨2, ⋯⟩ : R₁.obj (⟨2, ⋯⟩ : Fin (HAdd.hAdd (α := ℕ) 3 1)) ⟶ R₂.obj ⟨2, ⋯⟩) :
      A₁ ⟶ R₂.obj ⟨2, ⋯⟩)
    (0 : A₁ ⟶ R₂.obj ⟨2, ⋯⟩)
⊢ Eq (α := A₁ ⟶ R₂.obj ⟨2, ⋯⟩)
    (CategoryStruct.comp (Y := R₂.obj' 1 ⋯) (f₁ ≫ app' φ 1 ⋯) (R₂.map' 1 2 ⋯ ⋯) : A₁ ⟶ R₂.obj ⟨2, ⋯⟩)
    (0 : A₁ ⟶ R₂.obj ⟨2, ⋯⟩)
have rw₂ : π₁ ≫ f₂ ≫ φ.app (⟨2, sorry⟩ : Fin (HAdd.hAdd (α := ℕ) 3 1)) = 0
Tactic: rw [assoc, ← NatTrans.naturality, ← reassoc_of% hf₁, h₁, comp_zero]
-- Lean 4 proof step from Mathlib.CategoryTheory.Abelian.DiagramLemmas.Four (goal)
Goal:
C : Type u_1
inst : Category.{v_1, u_1} C
inst_1 : Abelian.{v_1, u_1} C
R₁ R₂ : ComposableArrows.{v_1, u_1} C 3
φ : R₁ ⟶ R₂
hR₁ : R₁.map' 0 2 mono_of_epi_of_mono_of_mono'._proof_2 mono_of_epi_of_mono_of_mono'._proof_4 = 0
hR₁' :
  (mk₂ (R₁.map' 1 2 mono_of_epi_of_mono_of_mono'._proof_6 mono_of_epi_of_mono_of_mono'._proof_4)
      (R₁.map' 2 3 mono_of_epi_of_mono_of_mono'._proof_4 mono_of_epi_of_mono_of_mono'._proof_7)).Exact
hR₂ :
  (mk₂ (R₂.map' 0 1 mono_of_epi_of_mono_of_mono'._proof_9 mono_of_epi_of_mono_of_mono'._proof_11)
      (R₂.map' 1 2 mono_of_epi_of_mono_of_mono'._proof_6 mono_of_epi_of_mono_of_mono'._proof_4)).Exact
h₀ : Epi (app' φ 0 mono_of_epi_of_mono_of_mono'._proof_13)
h₁_1 : Mono (app' φ 1 mono_of_epi_of_mono_of_mono'._proof_11)
h₃ : Mono (app' φ 3 mono_of_epi_of_mono_of_mono'._proof_7)
A : C
f₂ : A ⟶ R₁.obj' 2 mono_of_epi_of_mono_of_mono'._proof_4
h₁ : f₂ ≫ app' φ 2 mono_of_epi_of_mono_of_mono'._proof_4 = 0
h₂ : f₂ ≫ R₁.map' 2 3 ⋯ ⋯ = 0
A₁ : C
π₁ : A₁ ⟶ A
w : Epi π₁
f₁ :
  A₁ ⟶
    ((mk₂ (R₁.map' 1 2 mono_of_epi_of_mono_of_mono'._proof_6 mono_of_epi_of_mono_of_mono'._proof_4)
            (R₁.map' 2 3 mono_of_epi_of_mono_of_mono'._proof_4 mono_of_epi_of_mono_of_mono'._proof_7)).sc
        ⋯ 0 ⋯).X₁
hf₁ : π₁ ≫ f₂ = f₁ ≫ R₁.map (homOfLE ⋯)
rw :
  Eq (α := A₁ ⟶ R₂.obj ⟨2, ⋯⟩)
    (f₁ ≫ CategoryStruct.comp (Y := R₂.obj' 1 ⋯) (app' φ 1 ⋯) (R₂.map' 1 2 ⋯ ⋯) : A₁ ⟶ R₂.obj ⟨2, ⋯⟩)
    (0 : A₁ ⟶ R₂.obj ⟨2, ⋯⟩)
rw₁ :
  Eq (α := A₁ ⟶ R₂.obj ⟨2, ⋯⟩)
    (f₁ ≫
        CategoryStruct.comp (Y := R₁.obj ⟨2, ⋯⟩)
          (R₁.map (homOfLE ⋯) : R₁.obj (⟨1, ⋯⟩ : Fin (HAdd.hAdd (α := ℕ) 3 1)) ⟶ R₁.obj ⟨2, ⋯⟩)
          (φ.app ⟨2, ⋯⟩ : R₁.obj (⟨2, ⋯⟩ : Fin (HAdd.hAdd (α := ℕ) 3 1)) ⟶ R₂.obj ⟨2, ⋯⟩) :
      A₁ ⟶ R₂.obj ⟨2, ⋯⟩)
    (0 : A₁ ⟶ R₂.obj ⟨2, ⋯⟩)
rw₂ : π₁ ≫ f₂ ≫ φ.app (⟨2, ⋯⟩ : Fin (HAdd.hAdd (α := ℕ) 3 1)) = 0
⊢ Eq (α := A₁ ⟶ R₂.obj ⟨2, ⋯⟩)
    (CategoryStruct.comp (Y := R₂.obj' 1 ⋯) (f₁ ≫ app' φ 1 ⋯) (R₂.map' 1 2 ⋯ ⋯) : A₁ ⟶ R₂.obj ⟨2, ⋯⟩)
    (0 : A₁ ⟶ R₂.obj ⟨2, ⋯⟩)
have rw₃ : Eq (α := A₁ ⟶ R₂.obj ⟨2, sorry⟩) (π₁ ≫ 0) 0
Tactic: rw [assoc, ← NatTrans.naturality, ← reassoc_of% hf₁, h₁, comp_zero]
-- Lean 4 proof step from Mathlib.CategoryTheory.Abelian.DiagramLemmas.Four (goal)
Goal:
C : Type u_1
inst : Category.{v_1, u_1} C
inst_1 : Abelian.{v_1, u_1} C
R₁ R₂ : ComposableArrows.{v_1, u_1} C 3
φ : R₁ ⟶ R₂
hR₁ : R₁.map' 0 2 mono_of_epi_of_mono_of_mono'._proof_2 mono_of_epi_of_mono_of_mono'._proof_4 = 0
hR₁' :
  (mk₂ (R₁.map' 1 2 mono_of_epi_of_mono_of_mono'._proof_6 mono_of_epi_of_mono_of_mono'._proof_4)
      (R₁.map' 2 3 mono_of_epi_of_mono_of_mono'._proof_4 mono_of_epi_of_mono_of_mono'._proof_7)).Exact
hR₂ :
  (mk₂ (R₂.map' 0 1 mono_of_epi_of_mono_of_mono'._proof_9 mono_of_epi_of_mono_of_mono'._proof_11)
      (R₂.map' 1 2 mono_of_epi_of_mono_of_mono'._proof_6 mono_of_epi_of_mono_of_mono'._proof_4)).Exact
h₀ : Epi (app' φ 0 mono_of_epi_of_mono_of_mono'._proof_13)
h₁_1 : Mono (app' φ 1 mono_of_epi_of_mono_of_mono'._proof_11)
h₃ : Mono (app' φ 3 mono_of_epi_of_mono_of_mono'._proof_7)
A : C
f₂ : A ⟶ R₁.obj' 2 mono_of_epi_of_mono_of_mono'._proof_4
h₁ : f₂ ≫ app' φ 2 mono_of_epi_of_mono_of_mono'._proof_4 = 0
h₂ : f₂ ≫ R₁.map' 2 3 ⋯ ⋯ = 0
A₁ : C
π₁ : A₁ ⟶ A
w : Epi π₁
f₁ :
  A₁ ⟶
    ((mk₂ (R₁.map' 1 2 mono_of_epi_of_mono_of_mono'._proof_6 mono_of_epi_of_mono_of_mono'._proof_4)
            (R₁.map' 2 3 mono_of_epi_of_mono_of_mono'._proof_4 mono_of_epi_of_mono_of_mono'._proof_7)).sc
        ⋯ 0 ⋯).X₁
hf₁ : π₁ ≫ f₂ = f₁ ≫ R₁.map (homOfLE ⋯)
rw :
  Eq (α := A₁ ⟶ R₂.obj ⟨2, ⋯⟩)
    (f₁ ≫ CategoryStruct.comp (Y := R₂.obj' 1 ⋯) (app' φ 1 ⋯) (R₂.map' 1 2 ⋯ ⋯) : A₁ ⟶ R₂.obj ⟨2, ⋯⟩)
    (0 : A₁ ⟶ R₂.obj ⟨2, ⋯⟩)
rw₁ :
  Eq (α := A₁ ⟶ R₂.obj ⟨2, ⋯⟩)
    (f₁ ≫
        CategoryStruct.comp (Y := R₁.obj ⟨2, ⋯⟩)
          (R₁.map (homOfLE ⋯) : R₁.obj (⟨1, ⋯⟩ : Fin (HAdd.hAdd (α := ℕ) 3 1)) ⟶ R₁.obj ⟨2, ⋯⟩)
          (φ.app ⟨2, ⋯⟩ : R₁.obj (⟨2, ⋯⟩ : Fin (HAdd.hAdd (α := ℕ) 3 1)) ⟶ R₂.obj ⟨2, ⋯⟩) :
      A₁ ⟶ R₂.obj ⟨2, ⋯⟩)
    (0 : A₁ ⟶ R₂.obj ⟨2, ⋯⟩)
rw₂ : π₁ ≫ f₂ ≫ φ.app (⟨2, ⋯⟩ : Fin (HAdd.hAdd (α := ℕ) 3 1)) = 0
rw₃ : Eq (α := A₁ ⟶ R₂.obj ⟨2, ⋯⟩) (π₁ ≫ 0) 0
⊢ Eq (α := A₁ ⟶ R₂.obj ⟨2, ⋯⟩)
    (CategoryStruct.comp (Y := R₂.obj' 1 ⋯) (f₁ ≫ app' φ 1 ⋯) (R₂.map' 1 2 ⋯ ⋯) : A₁ ⟶ R₂.obj ⟨2, ⋯⟩)
    (0 : A₁ ⟶ R₂.obj ⟨2, ⋯⟩)
have rw₄ : Eq.{v_1 + 1} (α := A₁ ⟶ R₂.obj ⟨2, sorry⟩) 0 0
Tactic: rw [assoc, ← NatTrans.naturality, ← reassoc_of% hf₁, h₁, comp_zero]
-- Lean 4 proof step from Mathlib.CategoryTheory.Abelian.DiagramLemmas.Four (hypothesis)
Goal:
C : Type u_1
inst : Category.{v_1, u_1} C
inst_1 : Abelian.{v_1, u_1} C
R₁ R₂ : ComposableArrows.{v_1, u_1} C 3
φ : R₁ ⟶ R₂
hR₁ : R₁.map' 0 2 mono_of_epi_of_mono_of_mono'._proof_2 mono_of_epi_of_mono_of_mono'._proof_4 = 0
hR₁' :
  (mk₂ (R₁.map' 1 2 mono_of_epi_of_mono_of_mono'._proof_6 mono_of_epi_of_mono_of_mono'._proof_4)
      (R₁.map' 2 3 mono_of_epi_of_mono_of_mono'._proof_4 mono_of_epi_of_mono_of_mono'._proof_7)).Exact
hR₂ :
  (mk₂ (R₂.map' 0 1 mono_of_epi_of_mono_of_mono'._proof_9 mono_of_epi_of_mono_of_mono'._proof_11)
      (R₂.map' 1 2 mono_of_epi_of_mono_of_mono'._proof_6 mono_of_epi_of_mono_of_mono'._proof_4)).Exact
h₀ : Epi (app' φ 0 mono_of_epi_of_mono_of_mono'._proof_13)
h₁_1 : Mono (app' φ 1 mono_of_epi_of_mono_of_mono'._proof_11)
h₃ : Mono (app' φ 3 mono_of_epi_of_mono_of_mono'._proof_7)
A : C
f₂ : A ⟶ R₁.obj' 2 mono_of_epi_of_mono_of_mono'._proof_4
h₁ : f₂ ≫ app' φ 2 mono_of_epi_of_mono_of_mono'._proof_4 = 0
h₂ : f₂ ≫ R₁.map' 2 3 ⋯ ⋯ = 0
A₁ : C
π₁ : A₁ ⟶ A
w : Epi π₁
f₁ :
  A₁ ⟶
    ((mk₂ (R₁.map' 1 2 mono_of_epi_of_mono_of_mono'._proof_6 mono_of_epi_of_mono_of_mono'._proof_4)
            (R₁.map' 2 3 mono_of_epi_of_mono_of_mono'._proof_4 mono_of_epi_of_mono_of_mono'._proof_7)).sc
        ⋯ 0 ⋯).X₁
hf₁ : π₁ ≫ f₂ = f₁ ≫ R₁.map (homOfLE ⋯)
⊢ f₂ = 0
have h₄ : Eq (α := A₁ ⟶ R₂.obj ⟨2, sorry⟩)
  (CategoryStruct.comp (Y := R₂.obj' 1 sorry) (f₁ ≫ app' φ 1 sorry) (R₂.map' 1 2 sorry sorry) : A₁ ⟶ R₂.obj ⟨2, sorry⟩)
  (0 : A₁ ⟶ R₂.obj ⟨2, sorry⟩)
Tactic: have h₃ : (f₁ ≫ app' φ 1) ≫ R₂.map' 1 2 = 0 := by
    rw [assoc, ← NatTrans.naturality, ← reassoc_of% hf₁, h₁, comp_zero]
-- Lean 4 proof step from Mathlib.CategoryTheory.Abelian.DiagramLemmas.Four (goal)
Goal:
C : Type u_1
inst : Category.{v_1, u_1} C
inst_1 : Abelian.{v_1, u_1} C
R₁ R₂ : ComposableArrows.{v_1, u_1} C 3
φ : R₁ ⟶ R₂
hR₁ : R₁.map' 0 2 mono_of_epi_of_mono_of_mono'._proof_2 mono_of_epi_of_mono_of_mono'._proof_4 = 0
hR₁' :
  (mk₂ (R₁.map' 1 2 mono_of_epi_of_mono_of_mono'._proof_6 mono_of_epi_of_mono_of_mono'._proof_4)
      (R₁.map' 2 3 mono_of_epi_of_mono_of_mono'._proof_4 mono_of_epi_of_mono_of_mono'._proof_7)).Exact
hR₂ :
  (mk₂ (R₂.map' 0 1 mono_of_epi_of_mono_of_mono'._proof_9 mono_of_epi_of_mono_of_mono'._proof_11)
      (R₂.map' 1 2 mono_of_epi_of_mono_of_mono'._proof_6 mono_of_epi_of_mono_of_mono'._proof_4)).Exact
h₀ : Epi (app' φ 0 mono_of_epi_of_mono_of_mono'._proof_13)
h₁_1 : Mono (app' φ 1 mono_of_epi_of_mono_of_mono'._proof_11)
h₃_1 : Mono (app' φ 3 mono_of_epi_of_mono_of_mono'._proof_7)
A : C
f₂ : A ⟶ R₁.obj' 2 mono_of_epi_of_mono_of_mono'._proof_4
h₁ : f₂ ≫ app' φ 2 mono_of_epi_of_mono_of_mono'._proof_4 = 0
h₂ : f₂ ≫ R₁.map' 2 3 ⋯ ⋯ = 0
A₁ : C
π₁ : A₁ ⟶ A
w : Epi π₁
f₁ :
  A₁ ⟶
    ((mk₂ (R₁.map' 1 2 mono_of_epi_of_mono_of_mono'._proof_6 mono_of_epi_of_mono_of_mono'._proof_4)
            (R₁.map' 2 3 mono_of_epi_of_mono_of_mono'._proof_4 mono_of_epi_of_mono_of_mono'._proof_7)).sc
        ⋯ 0 ⋯).X₁
hf₁ : π₁ ≫ f₂ = f₁ ≫ R₁.map (homOfLE ⋯)
h₃ :
  Eq (α := A₁ ⟶ R₂.obj ⟨2, ⋯⟩)
    (CategoryStruct.comp (Y := R₂.obj' 1 ⋯) (f₁ ≫ app' φ 1 ⋯) (R₂.map' 1 2 ⋯ ⋯) : A₁ ⟶ R₂.obj ⟨2, ⋯⟩)
    (0 : A₁ ⟶ R₂.obj ⟨2, ⋯⟩)
⊢ f₂ = 0
have h : ∀ (A₂ : C) (π₂ : A₂ ⟶ A₁),
  Epi π₂ →
    ∀
      (g₀ :
        A₂ ⟶
          ((mk₂ (R₂.map' 0 1 mono_of_epi_of_mono_of_mono'._proof_9 mono_of_epi_of_mono_of_mono'._proof_11)
                  (R₂.map' 1 2 mono_of_epi_of_mono_of_mono'._proof_6 mono_of_epi_of_mono_of_mono'._proof_4)).sc
              sorry 0 sorry).X₁)
      (hg₀ :
        π₂ ≫ f₁ ≫ app' φ 1 sorry =
          g₀ ≫
            ((mk₂ (R₂.map' 0 1 mono_of_epi_of_mono_of_mono'._proof_9 mono_of_epi_of_mono_of_mono'._proof_11)
                    (R₂.map' 1 2 mono_of_epi_of_mono_of_mono'._proof_6 mono_of_epi_of_mono_of_mono'._proof_4)).sc
                sorry 0 sorry).f),
      f₂ = 0
Tactic: obtain ⟨A₂, π₂, _, g₀, hg₀⟩ := (hR₂.exact 0).exact_up_to_refinements _ h₃
-- Lean 4 proof step from Mathlib.CategoryTheory.Abelian.DiagramLemmas.Four (goal)
Goal:
C : Type u_1
inst : Category.{v_1, u_1} C
inst_1 : Abelian.{v_1, u_1} C
R₁ R₂ : ComposableArrows.{v_1, u_1} C 3
φ : R₁ ⟶ R₂
hR₁ : R₁.map' 0 2 mono_of_epi_of_mono_of_mono'._proof_2 mono_of_epi_of_mono_of_mono'._proof_4 = 0
hR₁' :
  (mk₂ (R₁.map' 1 2 mono_of_epi_of_mono_of_mono'._proof_6 mono_of_epi_of_mono_of_mono'._proof_4)
      (R₁.map' 2 3 mono_of_epi_of_mono_of_mono'._proof_4 mono_of_epi_of_mono_of_mono'._proof_7)).Exact
hR₂ :
  (mk₂ (R₂.map' 0 1 mono_of_epi_of_mono_of_mono'._proof_9 mono_of_epi_of_mono_of_mono'._proof_11)
      (R₂.map' 1 2 mono_of_epi_of_mono_of_mono'._proof_6 mono_of_epi_of_mono_of_mono'._proof_4)).Exact
h₀ : Epi (app' φ 0 mono_of_epi_of_mono_of_mono'._proof_13)
h₁_1 : Mono (app' φ 1 mono_of_epi_of_mono_of_mono'._proof_11)
h₃_1 : Mono (app' φ 3 mono_of_epi_of_mono_of_mono'._proof_7)
A : C
f₂ : A ⟶ R₁.obj' 2 mono_of_epi_of_mono_of_mono'._proof_4
h₁ : f₂ ≫ app' φ 2 mono_of_epi_of_mono_of_mono'._proof_4 = 0
h₂ : f₂ ≫ R₁.map' 2 3 ⋯ ⋯ = 0
A₁ : C
π₁ : A₁ ⟶ A
w : Epi π₁
f₁ :
  A₁ ⟶
    ((mk₂ (R₁.map' 1 2 mono_of_epi_of_mono_of_mono'._proof_6 mono_of_epi_of_mono_of_mono'._proof_4)
            (R₁.map' 2 3 mono_of_epi_of_mono_of_mono'._proof_4 mono_of_epi_of_mono_of_mono'._proof_7)).sc
        ⋯ 0 ⋯).X₁
hf₁ : π₁ ≫ f₂ = f₁ ≫ R₁.map (homOfLE ⋯)
h₃ :
  Eq (α := A₁ ⟶ R₂.obj ⟨2, ⋯⟩)
    (CategoryStruct.comp (Y := R₂.obj' 1 ⋯) (f₁ ≫ app' φ 1 ⋯) (R₂.map' 1 2 ⋯ ⋯) : A₁ ⟶ R₂.obj ⟨2, ⋯⟩)
    (0 : A₁ ⟶ R₂.obj ⟨2, ⋯⟩)
A₂ : C
π₂ : A₂ ⟶ A₁
w_1 : Epi π₂
g₀ :
  A₂ ⟶
    ((mk₂ (R₂.map' 0 1 mono_of_epi_of_mono_of_mono'._proof_9 mono_of_epi_of_mono_of_mono'._proof_11)
            (R₂.map' 1 2 mono_of_epi_of_mono_of_mono'._proof_6 mono_of_epi_of_mono_of_mono'._proof_4)).sc
        ⋯ 0 ⋯).X₁
hg₀ :
  π₂ ≫ f₁ ≫ app' φ 1 ⋯ =
    g₀ ≫
      ((mk₂ (R₂.map' 0 1 mono_of_epi_of_mono_of_mono'._proof_9 mono_of_epi_of_mono_of_mono'._proof_11)
              (R₂.map' 1 2 mono_of_epi_of_mono_of_mono'._proof_6 mono_of_epi_of_mono_of_mono'._proof_4)).sc
          ⋯ 0 ⋯).f
⊢ f₂ = 0
have h : ∀ (A₃ : C) (π₃ : A₃ ⟶ A₂),
  Epi π₃ →
    ∀ (f₀ : A₃ ⟶ R₁.obj' 0 mono_of_epi_of_mono_of_mono'._proof_13)
      (hf₀ : π₃ ≫ g₀ = f₀ ≫ app' φ 0 mono_of_epi_of_mono_of_mono'._proof_13), f₂ = 0
Tactic: obtain ⟨A₃, π₃, _, f₀, hf₀⟩ := surjective_up_to_refinements_of_epi (app' φ 0 _) g₀
-- Lean 4 proof step from Mathlib.CategoryTheory.Abelian.DiagramLemmas.Four (goal)
Goal:
C : Type u_1
inst : Category.{v_1, u_1} C
inst_1 : Abelian.{v_1, u_1} C
R₁ R₂ : ComposableArrows.{v_1, u_1} C 3
φ : R₁ ⟶ R₂
hR₁ : R₁.map' 0 2 mono_of_epi_of_mono_of_mono'._proof_2 mono_of_epi_of_mono_of_mono'._proof_4 = 0
hR₁' :
  (mk₂ (R₁.map' 1 2 mono_of_epi_of_mono_of_mono'._proof_6 mono_of_epi_of_mono_of_mono'._proof_4)
      (R₁.map' 2 3 mono_of_epi_of_mono_of_mono'._proof_4 mono_of_epi_of_mono_of_mono'._proof_7)).Exact
hR₂ :
  (mk₂ (R₂.map' 0 1 mono_of_epi_of_mono_of_mono'._proof_9 mono_of_epi_of_mono_of_mono'._proof_11)
      (R₂.map' 1 2 mono_of_epi_of_mono_of_mono'._proof_6 mono_of_epi_of_mono_of_mono'._proof_4)).Exact
h₀ : Epi (app' φ 0 mono_of_epi_of_mono_of_mono'._proof_13)
h₁_1 : Mono (app' φ 1 mono_of_epi_of_mono_of_mono'._proof_11)
h₃_1 : Mono (app' φ 3 mono_of_epi_of_mono_of_mono'._proof_7)
A : C
f₂ : A ⟶ R₁.obj' 2 mono_of_epi_of_mono_of_mono'._proof_4
h₁ : f₂ ≫ app' φ 2 mono_of_epi_of_mono_of_mono'._proof_4 = 0
h₂ : f₂ ≫ R₁.map' 2 3 ⋯ ⋯ = 0
A₁ : C
π₁ : A₁ ⟶ A
w : Epi π₁
f₁ :
  A₁ ⟶
    ((mk₂ (R₁.map' 1 2 mono_of_epi_of_mono_of_mono'._proof_6 mono_of_epi_of_mono_of_mono'._proof_4)
            (R₁.map' 2 3 mono_of_epi_of_mono_of_mono'._proof_4 mono_of_epi_of_mono_of_mono'._proof_7)).sc
        ⋯ 0 ⋯).X₁
hf₁ : π₁ ≫ f₂ = f₁ ≫ R₁.map (homOfLE ⋯)
h₃ :
  Eq (α := A₁ ⟶ R₂.obj ⟨2, ⋯⟩)
    (CategoryStruct.comp (Y := R₂.obj' 1 ⋯) (f₁ ≫ app' φ 1 ⋯) (R₂.map' 1 2 ⋯ ⋯) : A₁ ⟶ R₂.obj ⟨2, ⋯⟩)
    (0 : A₁ ⟶ R₂.obj ⟨2, ⋯⟩)
A₂ : C
π₂ : A₂ ⟶ A₁
w_1 : Epi π₂
g₀ :
  A₂ ⟶
    ((mk₂ (R₂.map' 0 1 mono_of_epi_of_mono_of_mono'._proof_9 mono_of_epi_of_mono_of_mono'._proof_11)
            (R₂.map' 1 2 mono_of_epi_of_mono_of_mono'._proof_6 mono_of_epi_of_mono_of_mono'._proof_4)).sc
        ⋯ 0 ⋯).X₁
hg₀ :
  π₂ ≫ f₁ ≫ app' φ 1 ⋯ =
    g₀ ≫
      ((mk₂ (R₂.map' 0 1 mono_of_epi_of_mono_of_mono'._proof_9 mono_of_epi_of_mono_of_mono'._proof_11)
              (R₂.map' 1 2 mono_of_epi_of_mono_of_mono'._proof_6 mono_of_epi_of_mono_of_mono'._proof_4)).sc
          ⋯ 0 ⋯).f
A₃ : C
π₃ : A₃ ⟶ A₂
w_2 : Epi π₃
f₀ : A₃ ⟶ R₁.obj' 0 mono_of_epi_of_mono_of_mono'._proof_13
hf₀ : π₃ ≫ g₀ = f₀ ≫ app' φ 0 mono_of_epi_of_mono_of_mono'._proof_13
⊢ f₀ ≫ R₁.map' 0 1 ⋯ ⋯ = π₃ ≫ π₂ ≫ f₁
have rw : π₃ ≫ g₀ ≫ R₂.map (homOfLE sorry) =
  π₃ ≫
    g₀ ≫
      ((mk₂ (R₂.map' 0 1 mono_of_epi_of_mono_of_mono'._proof_9 mono_of_epi_of_mono_of_mono'._proof_11)
              (R₂.map' 1 2 mono_of_epi_of_mono_of_mono'._proof_6 mono_of_epi_of_mono_of_mono'._proof_4)).sc
          sorry 0 sorry).f
Tactic: rw [← cancel_mono (app' φ 1 _), assoc, assoc, assoc, NatTrans.naturality,
      ← reassoc_of% hf₀, hg₀]
-- Lean 4 proof step from Mathlib.CategoryTheory.Abelian.DiagramLemmas.Four (hypothesis)
Goal:
C : Type u_1
inst : Category.{v_1, u_1} C
inst_1 : Abelian.{v_1, u_1} C
R₁ R₂ : ComposableArrows.{v_1, u_1} C 3
φ : R₁ ⟶ R₂
hR₁ : R₁.map' 0 2 mono_of_epi_of_mono_of_mono'._proof_2 mono_of_epi_of_mono_of_mono'._proof_4 = 0
hR₁' :
  (mk₂ (R₁.map' 1 2 mono_of_epi_of_mono_of_mono'._proof_6 mono_of_epi_of_mono_of_mono'._proof_4)
      (R₁.map' 2 3 mono_of_epi_of_mono_of_mono'._proof_4 mono_of_epi_of_mono_of_mono'._proof_7)).Exact
hR₂ :
  (mk₂ (R₂.map' 0 1 mono_of_epi_of_mono_of_mono'._proof_9 mono_of_epi_of_mono_of_mono'._proof_11)
      (R₂.map' 1 2 mono_of_epi_of_mono_of_mono'._proof_6 mono_of_epi_of_mono_of_mono'._proof_4)).Exact
h₀ : Epi (app' φ 0 mono_of_epi_of_mono_of_mono'._proof_13)
h₁_1 : Mono (app' φ 1 mono_of_epi_of_mono_of_mono'._proof_11)
h₃_1 : Mono (app' φ 3 mono_of_epi_of_mono_of_mono'._proof_7)
A : C
f₂ : A ⟶ R₁.obj' 2 mono_of_epi_of_mono_of_mono'._proof_4
h₁ : f₂ ≫ app' φ 2 mono_of_epi_of_mono_of_mono'._proof_4 = 0
h₂ : f₂ ≫ R₁.map' 2 3 ⋯ ⋯ = 0
A₁ : C
π₁ : A₁ ⟶ A
w : Epi π₁
f₁ :
  A₁ ⟶
    ((mk₂ (R₁.map' 1 2 mono_of_epi_of_mono_of_mono'._proof_6 mono_of_epi_of_mono_of_mono'._proof_4)
            (R₁.map' 2 3 mono_of_epi_of_mono_of_mono'._proof_4 mono_of_epi_of_mono_of_mono'._proof_7)).sc
        ⋯ 0 ⋯).X₁
hf₁ : π₁ ≫ f₂ = f₁ ≫ R₁.map (homOfLE ⋯)
h₃ :
  Eq (α := A₁ ⟶ R₂.obj ⟨2, ⋯⟩)
    (CategoryStruct.comp (Y := R₂.obj' 1 ⋯) (f₁ ≫ app' φ 1 ⋯) (R₂.map' 1 2 ⋯ ⋯) : A₁ ⟶ R₂.obj ⟨2, ⋯⟩)
    (0 : A₁ ⟶ R₂.obj ⟨2, ⋯⟩)
A₂ : C
π₂ : A₂ ⟶ A₁
w_1 : Epi π₂
g₀ :
  A₂ ⟶
    ((mk₂ (R₂.map' 0 1 mono_of_epi_of_mono_of_mono'._proof_9 mono_of_epi_of_mono_of_mono'._proof_11)
            (R₂.map' 1 2 mono_of_epi_of_mono_of_mono'._proof_6 mono_of_epi_of_mono_of_mono'._proof_4)).sc
        ⋯ 0 ⋯).X₁
hg₀ :
  π₂ ≫ f₁ ≫ app' φ 1 ⋯ =
    g₀ ≫
      ((mk₂ (R₂.map' 0 1 mono_of_epi_of_mono_of_mono'._proof_9 mono_of_epi_of_mono_of_mono'._proof_11)
              (R₂.map' 1 2 mono_of_epi_of_mono_of_mono'._proof_6 mono_of_epi_of_mono_of_mono'._proof_4)).sc
          ⋯ 0 ⋯).f
A₃ : C
π₃ : A₃ ⟶ A₂
w_2 : Epi π₃
f₀ : A₃ ⟶ R₁.obj' 0 mono_of_epi_of_mono_of_mono'._proof_13
hf₀ : π₃ ≫ g₀ = f₀ ≫ app' φ 0 mono_of_epi_of_mono_of_mono'._proof_13
⊢ f₂ = 0
have h₄ : f₀ ≫ R₁.map' 0 1 sorry sorry = π₃ ≫ π₂ ≫ f₁
Tactic: have h₄ : f₀ ≫ R₁.map' 0 1 = π₃ ≫ π₂ ≫ f₁ := by
    rw [← cancel_mono (app' φ 1 _), assoc, assoc, assoc, NatTrans.naturality,
      ← reassoc_of% hf₀, hg₀]
    rfl
-- Lean 4 proof step from Mathlib.CategoryTheory.Abelian.DiagramLemmas.Four (goal)
Goal:
C : Type u_1
inst : Category.{v_1, u_1} C
inst_1 : Abelian.{v_1, u_1} C
R₁ R₂ : ComposableArrows.{v_1, u_1} C 3
φ : R₁ ⟶ R₂
hR₁ : R₁.map' 0 2 mono_of_epi_of_mono_of_mono'._proof_2 mono_of_epi_of_mono_of_mono'._proof_4 = 0
hR₁' :
  (mk₂ (R₁.map' 1 2 mono_of_epi_of_mono_of_mono'._proof_6 mono_of_epi_of_mono_of_mono'._proof_4)
      (R₁.map' 2 3 mono_of_epi_of_mono_of_mono'._proof_4 mono_of_epi_of_mono_of_mono'._proof_7)).Exact
hR₂ :
  (mk₂ (R₂.map' 0 1 mono_of_epi_of_mono_of_mono'._proof_9 mono_of_epi_of_mono_of_mono'._proof_11)
      (R₂.map' 1 2 mono_of_epi_of_mono_of_mono'._proof_6 mono_of_epi_of_mono_of_mono'._proof_4)).Exact
h₀ : Epi (app' φ 0 mono_of_epi_of_mono_of_mono'._proof_13)
h₁_1 : Mono (app' φ 1 mono_of_epi_of_mono_of_mono'._proof_11)
h₃_1 : Mono (app' φ 3 mono_of_epi_of_mono_of_mono'._proof_7)
A : C
f₂ : A ⟶ R₁.obj' 2 mono_of_epi_of_mono_of_mono'._proof_4
h₁ : f₂ ≫ app' φ 2 mono_of_epi_of_mono_of_mono'._proof_4 = 0
h₂ : f₂ ≫ R₁.map' 2 3 ⋯ ⋯ = 0
A₁ : C
π₁ : A₁ ⟶ A
w : Epi π₁
f₁ :
  A₁ ⟶
    ((mk₂ (R₁.map' 1 2 mono_of_epi_of_mono_of_mono'._proof_6 mono_of_epi_of_mono_of_mono'._proof_4)
            (R₁.map' 2 3 mono_of_epi_of_mono_of_mono'._proof_4 mono_of_epi_of_mono_of_mono'._proof_7)).sc
        ⋯ 0 ⋯).X₁
hf₁ : π₁ ≫ f₂ = f₁ ≫ R₁.map (homOfLE ⋯)
h₃ :
  Eq (α := A₁ ⟶ R₂.obj ⟨2, ⋯⟩)
    (CategoryStruct.comp (Y := R₂.obj' 1 ⋯) (f₁ ≫ app' φ 1 ⋯) (R₂.map' 1 2 ⋯ ⋯) : A₁ ⟶ R₂.obj ⟨2, ⋯⟩)
    (0 : A₁ ⟶ R₂.obj ⟨2, ⋯⟩)
A₂ : C
π₂ : A₂ ⟶ A₁
w_1 : Epi π₂
g₀ :
  A₂ ⟶
    ((mk₂ (R₂.map' 0 1 mono_of_epi_of_mono_of_mono'._proof_9 mono_of_epi_of_mono_of_mono'._proof_11)
            (R₂.map' 1 2 mono_of_epi_of_mono_of_mono'._proof_6 mono_of_epi_of_mono_of_mono'._proof_4)).sc
        ⋯ 0 ⋯).X₁
hg₀ :
  π₂ ≫ f₁ ≫ app' φ 1 ⋯ =
    g₀ ≫
      ((mk₂ (R₂.map' 0 1 mono_of_epi_of_mono_of_mono'._proof_9 mono_of_epi_of_mono_of_mono'._proof_11)
              (R₂.map' 1 2 mono_of_epi_of_mono_of_mono'._proof_6 mono_of_epi_of_mono_of_mono'._proof_4)).sc
          ⋯ 0 ⋯).f
A₃ : C
π₃ : A₃ ⟶ A₂
w_2 : Epi π₃
f₀ : A₃ ⟶ R₁.obj' 0 mono_of_epi_of_mono_of_mono'._proof_13
hf₀ : π₃ ≫ g₀ = f₀ ≫ app' φ 0 mono_of_epi_of_mono_of_mono'._proof_13
h₄ : f₀ ≫ R₁.map' 0 1 ⋯ ⋯ = π₃ ≫ π₂ ≫ f₁
⊢ f₂ = 0
have h : π₁ ≫ f₂ = π₁ ≫ 0
Tactic: rw [← cancel_epi π₁, comp_zero, hf₁, ← cancel_epi π₂, ← cancel_epi π₃, comp_zero,
    comp_zero, ← reassoc_of% h₄, ← R₁.map'_comp 0 1 2, hR₁, comp_zero]
-- Lean 4 proof step from Mathlib.CategoryTheory.Abelian.DiagramLemmas.Four (goal)
Goal:
C : Type u_1
inst : Category.{v_1, u_1} C
inst_1 : Abelian.{v_1, u_1} C
R₁ R₂ : ComposableArrows.{v_1, u_1} C 3
φ : R₁ ⟶ R₂
hR₁ : R₁.map' 0 2 mono_of_epi_of_mono_of_mono'._proof_2 mono_of_epi_of_mono_of_mono'._proof_4 = 0
hR₁' :
  (mk₂ (R₁.map' 1 2 mono_of_epi_of_mono_of_mono'._proof_6 mono_of_epi_of_mono_of_mono'._proof_4)
      (R₁.map' 2 3 mono_of_epi_of_mono_of_mono'._proof_4 mono_of_epi_of_mono_of_mono'._proof_7)).Exact
hR₂ :
  (mk₂ (R₂.map' 0 1 mono_of_epi_of_mono_of_mono'._proof_9 mono_of_epi_of_mono_of_mono'._proof_11)
      (R₂.map' 1 2 mono_of_epi_of_mono_of_mono'._proof_6 mono_of_epi_of_mono_of_mono'._proof_4)).Exact
h₀ : Epi (app' φ 0 mono_of_epi_of_mono_of_mono'._proof_13)
h₁_1 : Mono (app' φ 1 mono_of_epi_of_mono_of_mono'._proof_11)
h₃_1 : Mono (app' φ 3 mono_of_epi_of_mono_of_mono'._proof_7)
A : C
f₂ : A ⟶ R₁.obj' 2 mono_of_epi_of_mono_of_mono'._proof_4
h₁ : f₂ ≫ app' φ 2 mono_of_epi_of_mono_of_mono'._proof_4 = 0
h₂ : f₂ ≫ R₁.map' 2 3 ⋯ ⋯ = 0
A₁ : C
π₁ : A₁ ⟶ A
w : Epi π₁
f₁ :
  A₁ ⟶
    ((mk₂ (R₁.map' 1 2 mono_of_epi_of_mono_of_mono'._proof_6 mono_of_epi_of_mono_of_mono'._proof_4)
            (R₁.map' 2 3 mono_of_epi_of_mono_of_mono'._proof_4 mono_of_epi_of_mono_of_mono'._proof_7)).sc
        ⋯ 0 ⋯).X₁
hf₁ : π₁ ≫ f₂ = f₁ ≫ R₁.map (homOfLE ⋯)
h₃ :
  Eq (α := A₁ ⟶ R₂.obj ⟨2, ⋯⟩)
    (CategoryStruct.comp (Y := R₂.obj' 1 ⋯) (f₁ ≫ app' φ 1 ⋯) (R₂.map' 1 2 ⋯ ⋯) : A₁ ⟶ R₂.obj ⟨2, ⋯⟩)
    (0 : A₁ ⟶ R₂.obj ⟨2, ⋯⟩)
A₂ : C
π₂ : A₂ ⟶ A₁
w_1 : Epi π₂
g₀ :
  A₂ ⟶
    ((mk₂ (R₂.map' 0 1 mono_of_epi_of_mono_of_mono'._proof_9 mono_of_epi_of_mono_of_mono'._proof_11)
            (R₂.map' 1 2 mono_of_epi_of_mono_of_mono'._proof_6 mono_of_epi_of_mono_of_mono'._proof_4)).sc
        ⋯ 0 ⋯).X₁
hg₀ :
  π₂ ≫ f₁ ≫ app' φ 1 ⋯ =
    g₀ ≫
      ((mk₂ (R₂.map' 0 1 mono_of_epi_of_mono_of_mono'._proof_9 mono_of_epi_of_mono_of_mono'._proof_11)
              (R₂.map' 1 2 mono_of_epi_of_mono_of_mono'._proof_6 mono_of_epi_of_mono_of_mono'._proof_4)).sc
          ⋯ 0 ⋯).f
A₃ : C
π₃ : A₃ ⟶ A₂
w_2 : Epi π₃
f₀ : A₃ ⟶ R₁.obj' 0 mono_of_epi_of_mono_of_mono'._proof_13
hf₀ : π₃ ≫ g₀ = f₀ ≫ app' φ 0 mono_of_epi_of_mono_of_mono'._proof_13
h₄ : f₀ ≫ R₁.map' 0 1 ⋯ ⋯ = π₃ ≫ π₂ ≫ f₁
h : π₁ ≫ f₂ = π₁ ≫ 0
⊢ f₂ = 0
have h₅ : π₁ ≫ f₂ = 0
Tactic: rw [← cancel_epi π₁, comp_zero, hf₁, ← cancel_epi π₂, ← cancel_epi π₃, comp_zero,
    comp_zero, ← reassoc_of% h₄, ← R₁.map'_comp 0 1 2, hR₁, comp_zero]