mathlib-initiative/mathlib-tactics huggingface dataset:
Module: Mathlib.Geometry.Manifold.VectorBundle.LocalFrame

Goal state before:
pp: 𝕜 : Type u_1
inst✝¹⁴ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝¹³ : NormedAddCommGroup E
inst✝¹² : NormedSpace 𝕜 E
H : Type u_3
inst✝¹¹ : TopologicalSpace H
I : ModelWithCorners 𝕜 E H
M : Type u_4
inst✝¹⁰ : TopologicalSpace M
inst✝⁹ : ChartedSpace H M
F : Type u_5
inst✝⁸ : NormedAddCommGroup F
inst✝⁷ : NormedSpace 𝕜 F
n✝ : ℕ∞ω
V : M → Type u_6
inst✝⁶ : TopologicalSpace (TotalSpace F V)
inst✝⁵ : (x : M) → AddCommGroup (V x)
inst✝⁴ : (x : M) → Module 𝕜 (V x)
inst✝³ : (x : M) → TopologicalSpace (V x)
inst✝² : FiberBundle F V
ι : Type u_7
s s' : ι → (x : M) → V x
u u' : Set M
x : M
n : ℕ∞ω
inst✝¹ : VectorBundle 𝕜 F V
inst✝ : FiniteDimensional 𝕜 F
hs : IsLocalFrameOn I F n s u
hx : x ∈ u
this : FiniteDimensional 𝕜 (V x)
⊢ Fintype ι

Tactic:
exact FiniteDimensional.fintypeBasisIndex (hs.toBasisAt hx)

Goal state after:
Module: Mathlib.Geometry.Manifold.VectorBundle.CovariantDerivative.Basic

Goal state before:
pp: 𝕜 : Type u_1
inst✝¹⁸ : NontriviallyNormedField 𝕜
E : Type u_2
inst✝¹⁷ : NormedAddCommGroup E
inst✝¹⁶ : NormedSpace 𝕜 E
H : Type u_3
inst✝¹⁵ : TopologicalSpace H
I : ModelWithCorners 𝕜 E H
M : Type u_4
inst✝¹⁴ : TopologicalSpace M
inst✝¹³ : ChartedSpace H M
F : Type u_5
inst✝¹² : NormedAddCommGroup F
inst✝¹¹ : NormedSpace 𝕜 F
V : M → Type u_6
inst✝¹⁰ : TopologicalSpace (TotalSpace F V)
inst✝⁹ : (x : M) → AddCommGroup (V x)
inst✝⁸ : (x : M) → Module 𝕜 (V x)
inst✝⁷ : (x : M) → TopologicalSpace (V x)
inst✝⁶ : ∀ (x : M), IsTopologicalAddGroup (V x)
inst✝⁵ : ∀ (x : M), ContinuousSMul 𝕜 (V x)
inst✝⁴ : FiberBundle F V
cov cov' : ((x : M) → V x) → (x : M) → TangentSpace I x →L[𝕜] V x
s : Set M
hcov : IsCovariantDerivativeOn F cov s
hcov' : IsCovariantDerivativeOn F cov' s
inst✝³ : CompleteSpace 𝕜
inst✝² : FiniteDimensional 𝕜 F
inst✝¹ : VectorBundle 𝕜 F V
inst✝ : ContMDiffVectorBundle 1 F V I
x : M
hx : x ∈ s
σ : (x : M) → V x
hσ : MDiffAt (T% σ) x
⊢ (hcov.difference hcov' x) (σ x) = cov σ x - cov' σ x

Tactic:
by
  simp only [difference, hx, reduceDIte]
  rw [TensorialAt.mkHom_apply _ hσ]
  rfl

Goal state after:
Module: Mathlib.GroupTheory.SpecificGroups.Dihedral

Goal state before:
pp: case sr
n : ℕ
a : ZMod n
⊢ 1 * sr a = sr a

Tactic:
exact congr_arg sr (sub_zero a)

Goal state after:
Module: Mathlib.GroupTheory.CommutingProbability

Goal state before:
pp: M : Type u_1
inst✝¹ : Mul M
M' : Type u_2
inst✝ : Mul M'
⊢ ↑(Nat.card { p // Commute p.1 p.2 }) / ↑(Nat.card (M × M')) ^ 2 =
    ↑(Nat.card { p // Commute p.1 p.2 }) / ↑(Nat.card M) ^ 2 *
      (↑(Nat.card { p // Commute p.1 p.2 }) / ↑(Nat.card M') ^ 2)

Tactic:
div_mul_div_comm,

Goal state after:
M : Type u_1
inst✝¹ : Mul M
M' : Type u_2
inst✝ : Mul M'
⊢ ↑(Nat.card { p // Commute p.1 p.2 }) / ↑(Nat.card (M × M')) ^ 2 =
    ↑(Nat.card { p // Commute p.1 p.2 }) * ↑(Nat.card { p // Commute p.1 p.2 }) /
      (↑(Nat.card M) ^ 2 * ↑(Nat.card M') ^ 2)
Module: Mathlib.GroupTheory.CommutingProbability

Goal state before:
pp: M : Type u_1
inst✝¹ : Mul M
M' : Type u_2
inst✝ : Mul M'
⊢ commProb (M × M') = commProb M * commProb M'

Tactic:
simp_rw [commProb_def, div_mul_div_comm, Nat.card_prod, Nat.cast_mul, mul_pow, ← Nat.cast_mul,
    ← Nat.card_prod, Commute, SemiconjBy, Prod.ext_iff]
  congr 2
  exact Nat.card_congr ⟨fun x => ⟨⟨⟨x.1.1.1, x.1.2.1⟩, x.2.1⟩, ⟨⟨x.1.1.2, x.1.2.2⟩, x.2.2⟩⟩,
    fun x => ⟨⟨⟨x.1.1.1, x.2.1.1⟩, ⟨x.1.1.2, x.2.1.2⟩⟩, ⟨x.1.2, x.2.2⟩⟩, fun x => rfl, fun x => rfl⟩

Goal state after:
Module: Mathlib.GroupTheory.CommutingProbability

Goal state before:
pp: case neg.inr
n : ℕ
h0 : ¬n = 0
h1 : ¬n = 1
h2 : Odd n
hn : Odd (n % 4)
⊢ (↑(n % 4 * n) + 3) / (4 * ↑(n % 4 * n)) * (1 / ↑(n / 4 + 1)) = 1 / ↑n

Tactic:
div_mul_div_comm,

Goal state after:
case neg.inr
n : ℕ
h0 : ¬n = 0
h1 : ¬n = 1
h2 : Odd n
hn : Odd (n % 4)
⊢ (↑(n % 4 * n) + 3) * 1 / (4 * ↑(n % 4 * n) * ↑(n / 4 + 1)) = 1 / ↑n
Module: Mathlib.Topology.VectorBundle.Riemannian

Goal state before:
pp: B : Type u_1
inst✝⁷ : TopologicalSpace B
F : Type u_2
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace ℝ F
E : B → Type u_3
inst✝⁴ : TopologicalSpace (TotalSpace F E)
inst✝³ : (x : B) → NormedAddCommGroup (E x)
inst✝² : (x : B) → InnerProductSpace ℝ (E x)
inst✝¹ : FiberBundle F E
inst✝ : VectorBundle ℝ F E
h : IsContinuousRiemannianBundle F E
x : B
r : ℝ
hr : 1 < r
r' : ℝ
hr' : 1 < r'
r'r : r' < r
h'x : x ∈ (trivializationAt F E x).baseSet
G : E x ≃L[ℝ] F := Trivialization.continuousLinearEquivAt ℝ (trivializationAt F E x) x h'x
⊢ ∀ᶠ (y : B) in 𝓝 x,
    ‖Trivialization.symmL ℝ (trivializationAt F E x) y ∘SL
          Trivialization.continuousLinearMapAt ℝ (trivializationAt F E x) x‖ <
      r

Tactic:
let C := (‖(G : E x →L[ℝ] F)‖) ^ 2

Goal state after:
B : Type u_1
inst✝⁷ : TopologicalSpace B
F : Type u_2
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace ℝ F
E : B → Type u_3
inst✝⁴ : TopologicalSpace (TotalSpace F E)
inst✝³ : (x : B) → NormedAddCommGroup (E x)
inst✝² : (x : B) → InnerProductSpace ℝ (E x)
inst✝¹ : FiberBundle F E
inst✝ : VectorBundle ℝ F E
h : IsContinuousRiemannianBundle F E
x : B
r : ℝ
hr : 1 < r
r' : ℝ
hr' : 1 < r'
r'r : r' < r
h'x : x ∈ (trivializationAt F E x).baseSet
G : E x ≃L[ℝ] F := Trivialization.continuousLinearEquivAt ℝ (trivializationAt F E x) x h'x
C : ℝ := ‖↑G‖ ^ 2
⊢ ∀ᶠ (y : B) in 𝓝 x,
    ‖Trivialization.symmL ℝ (trivializationAt F E x) y ∘SL
          Trivialization.continuousLinearMapAt ℝ (trivializationAt F E x) x‖ <
      r
Module: Mathlib.GroupTheory.CoprodI

Goal state before:
pp: ι : Type u_1
M : ι → Type u_2
inst✝¹ : (i : ι) → Monoid (M i)
inst✝ : (i : ι) → DecidableEq (M i)
i : ι
m : M i
w : Word M
h : w.fstIdx ≠ some i
m' : M i
w' : Word M
h' : w'.fstIdx ≠ some i
he : rcons { head := m, tail := w, fstIdx_ne := h } = rcons { head := m', tail := w', fstIdx_ne := h' }
⊢ { head := m, tail := w, fstIdx_ne := h } = { head := m', tail := w', fstIdx_ne := h' }

Tactic:
by_cases hm : m = 1

Goal state after:
case pos
ι : Type u_1
M : ι → Type u_2
inst✝¹ : (i : ι) → Monoid (M i)
inst✝ : (i : ι) → DecidableEq (M i)
i : ι
m : M i
w : Word M
h : w.fstIdx ≠ some i
m' : M i
w' : Word M
h' : w'.fstIdx ≠ some i
he : rcons { head := m, tail := w, fstIdx_ne := h } = rcons { head := m', tail := w', fstIdx_ne := h' }
hm : m = 1
⊢ { head := m, tail := w, fstIdx_ne := h } = { head := m', tail := w', fstIdx_ne := h' }

case neg
ι : Type u_1
M : ι → Type u_2
inst✝¹ : (i : ι) → Monoid (M i)
inst✝ : (i : ι) → DecidableEq (M i)
i : ι
m : M i
w : Word M
h : w.fstIdx ≠ some i
m' : M i
w' : Word M
h' : w'.fstIdx ≠ some i
he : rcons { head := m, tail := w, fstIdx_ne := h } = rcons { head := m', tail := w', fstIdx_ne := h' }
hm : ¬m = 1
⊢ { head := m, tail := w, fstIdx_ne := h } = { head := m', tail := w', fstIdx_ne := h' }
Module: Mathlib.Topology.VectorBundle.Riemannian

Goal state before:
pp: B : Type u_1
inst✝⁷ : TopologicalSpace B
F : Type u_2
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace ℝ F
E : B → Type u_3
inst✝⁴ : TopologicalSpace (TotalSpace F E)
inst✝³ : (x : B) → NormedAddCommGroup (E x)
inst✝² : (x : B) → InnerProductSpace ℝ (E x)
inst✝¹ : FiberBundle F E
inst✝ : VectorBundle ℝ F E
h : IsContinuousRiemannianBundle F E
x : B
r : ℝ
hr : 1 < r
r' : ℝ
hr' : 1 < r'
r'r : r' < r
h'x : x ∈ (trivializationAt F E x).baseSet
G : E x ≃L[ℝ] F := Trivialization.continuousLinearEquivAt ℝ (trivializationAt F E x) x h'x
C : ℝ := ‖↑G‖ ^ 2
δ : ℝ
δpos : 0 < δ
h'δ : 1 + δ * C < r' ^ 2
g : (x : B) → E x →L[ℝ] E x →L[ℝ] ℝ
g_cont :
  Continuous[inst✝⁷, topologicalSpaceTotalSpace (RingHom.id ℝ) F E (F →L[ℝ] ℝ) fun x ↦ E x →L[ℝ] ℝ] fun x ↦
    TotalSpace.mk' (F →L[ℝ] F →L[ℝ] ℝ) x (g x)
hg : ∀ (x : B) (v w : E x), ⟪v, w⟫ = ((g x) v) w
g' : B → F →L[ℝ] F →L[ℝ] ℝ := fun y ↦ inCoordinates F E (F →L[ℝ] ℝ) (fun x ↦ E x →L[ℝ] ℝ) x y x y (g y)
hg' : ContinuousAt g' x
⊢ ∀ᶠ (y : B) in 𝓝 x, dist (g' y) (g' x) < δ

Tactic:
rw [Metric.continuousAt_iff'] at hg'

Goal state after:
B : Type u_1
inst✝⁷ : TopologicalSpace B
F : Type u_2
inst✝⁶ : NormedAddCommGroup F
inst✝⁵ : NormedSpace ℝ F
E : B → Type u_3
inst✝⁴ : TopologicalSpace (TotalSpace F E)
inst✝³ : (x : B) → NormedAddCommGroup (E x)
inst✝² : (x : B) → InnerProductSpace ℝ (E x)
inst✝¹ : FiberBundle F E
inst✝ : VectorBundle ℝ F E
h : IsContinuousRiemannianBundle F E
x : B
r : ℝ
hr : 1 < r
r' : ℝ
hr' : 1 < r'
r'r : r' < r
h'x : x ∈ (trivializationAt F E x).baseSet
G : E x ≃L[ℝ] F := Trivialization.continuousLinearEquivAt ℝ (trivializationAt F E x) x h'x
C : ℝ := ‖↑G‖ ^ 2
δ : ℝ
δpos : 0 < δ
h'δ : 1 + δ * C < r' ^ 2
g : (x : B) → E x →L[ℝ] E x →L[ℝ] ℝ
g_cont :
  Continuous[inst✝⁷, topologicalSpaceTotalSpace (RingHom.id ℝ) F E (F →L[ℝ] ℝ) fun x ↦ E x →L[ℝ] ℝ] fun x ↦
    TotalSpace.mk' (F →L[ℝ] F →L[ℝ] ℝ) x (g x)
hg : ∀ (x : B) (v w : E x), ⟪v, w⟫ = ((g x) v) w
g' : B → F →L[ℝ] F →L[ℝ] ℝ := fun y ↦ inCoordinates F E (F →L[ℝ] ℝ) (fun x ↦ E x →L[ℝ] ℝ) x y x y (g y)
hg' : ∀ ε > 0, ∀ᶠ (x_1 : B) in 𝓝 x, dist (g' x_1) (g' x) < ε
⊢ ∀ᶠ (y : B) in 𝓝 x, dist (g' y) (g' x) < δ
Module: Mathlib.GroupTheory.Coxeter.Inversion

Goal state before:
pp: B : Type u_1
W : Type u_2
inst✝ : Group W
M : CoxeterMatrix B
cs : CoxeterSystem M W
ω : List B
j : ℕ
⊢ cs.wordProd ω *
      ((cs.wordProd (drop (j + 1) ω))⁻¹ * (Option.map cs.simple ω[j]?).getD 1 * cs.wordProd (drop (j + 1) ω)) =
    cs.wordProd (take j ω ++ drop (j + 1) ω)

Tactic:
← take_append_drop (j + 1) ω

Goal state after:
B : Type u_1
W : Type u_2
inst✝ : Group W
M : CoxeterMatrix B
cs : CoxeterSystem M W
ω : List B
j : ℕ
⊢ cs.wordProd (take (j + 1) ω ++ drop (j + 1) ω) *
      ((cs.wordProd (drop (j + 1) ω))⁻¹ * (Option.map cs.simple ω[j]?).getD 1 * cs.wordProd (drop (j + 1) ω)) =
    cs.wordProd (take j ω ++ drop (j + 1) ω)
Module: Mathlib.GroupTheory.Coxeter.Inversion

Goal state before:
pp: B : Type u_1
W : Type u_2
inst✝ : Group W
M : CoxeterMatrix B
cs : CoxeterSystem M W
ω : List B
j : ℕ
⊢ cs.wordProd (take j ω) * (Option.map cs.simple ω[j]?).getD 1 * (cs.wordProd (take j ω))⁻¹ * cs.wordProd ω =
    cs.wordProd (take j ω ++ drop (j + 1) ω)

Tactic:
← take_append_drop (j + 1) ω

Goal state after:
B : Type u_1
W : Type u_2
inst✝ : Group W
M : CoxeterMatrix B
cs : CoxeterSystem M W
ω : List B
j : ℕ
⊢ cs.wordProd (take j ω) * (Option.map cs.simple ω[j]?).getD 1 * (cs.wordProd (take j ω))⁻¹ *
      cs.wordProd (take (j + 1) ω ++ drop (j + 1) ω) =
    cs.wordProd (take j ω ++ drop (j + 1) ω)
Module: Mathlib.GroupTheory.DoubleCoset

Goal state before:
pp: case mp
G : Type u_1
inst✝ : Group G
H K : Subgroup G
a x : G
y : ↥K
h_h : x * ((↑y)⁻¹ * a⁻¹) ∈ H
⊢ x = x * (↑y⁻¹ * a⁻¹) * a * ↑y

Tactic:
simp only [← mul_assoc, inv_mul_cancel_right, InvMemClass.coe_inv]

Goal state after:
Module: Mathlib.GroupTheory.DoubleCoset

Goal state before:
pp: G : Type u_1
inst✝ : Group G
H : Subgroup G
⊢ Quotient ↑⊥ ↑H = (G ⧸ H)

Tactic:
unfold Quotient
  congr
  ext
  simp_rw [← bot_rel_eq_leftRel H]

Goal state after:
Module: Mathlib.GroupTheory.CoprodI

Goal state before:
pp: ι✝ : Type u_1
M : ι✝ → Type u_2
inst✝¹ : (i : ι✝) → Monoid (M i)
N : Type u_3
inst✝ : Monoid N
ι : Type u_1
⊢ FreeGroup ι ≃* CoprodI fun x ↦ FreeGroup Unit

Tactic:
refine MonoidHom.toMulEquiv ?_ ?_ ?_ ?_
  · exact FreeGroup.lift fun i => @CoprodI.of ι _ _ i (FreeGroup.of Unit.unit)
  · exact CoprodI.lift fun i => FreeGroup.lift fun _ => FreeGroup.of i
  · ext; simp
  · ext i a; cases a; simp

Goal state after:
Module: Mathlib.GroupTheory.DivisibleHull

Goal state before:
pp: M : Type u_2
inst✝² : AddCommGroup M
inst✝¹ : LinearOrder M
inst✝ : IsOrderedAddMonoid M
m : M
s s' : ℕ+
this : ArchimedeanClass.mk (↑↑s • mk m s) = ArchimedeanClass.mk (↑↑s' • mk m s')
⊢ ArchimedeanClass.mk (mk m s) = ArchimedeanClass.mk (mk m s')

Tactic:
ArchimedeanClass.mk_smul _ (by simp)

Goal state after:
M : Type u_2
inst✝² : AddCommGroup M
inst✝¹ : LinearOrder M
inst✝ : IsOrderedAddMonoid M
m : M
s s' : ℕ+
this : ArchimedeanClass.mk (mk m s) = ArchimedeanClass.mk (↑↑s' • mk m s')
⊢ ArchimedeanClass.mk (mk m s) = ArchimedeanClass.mk (mk m s')
Module: Mathlib.GroupTheory.DivisibleHull

Goal state before:
pp: M : Type u_2
inst✝² : AddCommGroup M
inst✝¹ : LinearOrder M
inst✝ : IsOrderedAddMonoid M
m : M
s s' : ℕ+
this : ArchimedeanClass.mk (mk m s) = ArchimedeanClass.mk (↑↑s' • mk m s')
⊢ ArchimedeanClass.mk (mk m s) = ArchimedeanClass.mk (mk m s')

Tactic:
ArchimedeanClass.mk_smul _ (by simp)

Goal state after:
M : Type u_2
inst✝² : AddCommGroup M
inst✝¹ : LinearOrder M
inst✝ : IsOrderedAddMonoid M
m : M
s s' : ℕ+
this : ArchimedeanClass.mk (mk m s) = ArchimedeanClass.mk (mk m s')
⊢ ArchimedeanClass.mk (mk m s) = ArchimedeanClass.mk (mk m s')
Module: Mathlib.GroupTheory.CoprodI

Goal state before:

Tactic:
a i ^ n • X' j ⊆ a i ^ n • (Y i)ᶜ :=
          smul_set_mono ((hXYdisj j i).union_left <| hYdisj hij.symm).subset_compl_right
        _ ⊆ X i := by
          clear hnne0 hlt
          induction n, h1n using Int.leInduction with
          | base => rw [zpow_one]; exact hX i
          | succ n _hle hi =>
            calc
              a i ^ (n + 1) • (Y i)ᶜ = (a i ^ n * a i) • (Y i)ᶜ := by rw [zpow_add, zpow_one]
              _ = a i ^ n • a i • (Y i)ᶜ := mul_smul _ _ _
              _ ⊆ a i ^ n • X i := smul_set_mono <| hX i
              _ ⊆ a i ^ n • (Y i)ᶜ := smul_set_mono (hXYdisj i i).subset_compl_right
              _ ⊆ X i := hi
        _ ⊆ X' i := Set.subset_union_left

Goal state after:
Module: Mathlib.GroupTheory.CoprodI

Goal state before:
pp: case hpp.inl
ι : Type u_1
inst✝² : Nontrivial ι
G : Type u_1
inst✝¹ : Group G
a : ι → G
α : Type u_4
inst✝ : MulAction G α
X Y : ι → Set α
hXnonempty : ∀ (i : ι), (X i).Nonempty
hXdisj : Pairwise (Disjoint on X)
hYdisj : Pairwise (Disjoint on Y)
hXYdisj : ∀ (i j : ι), Disjoint (X i) (Y j)
hX : ∀ (i : ι), a i • (Y i)ᶜ ⊆ X i
hY : ∀ (i : ι), a⁻¹ i • (X i)ᶜ ⊆ Y i
H : ι → Type := fun _i ↦ FreeGroup Unit
f : (i : ι) → H i →* G := fun i ↦ FreeGroup.lift fun x ↦ a i
X' : ι → Set α := fun i ↦ X i ∪ Y i
i j : ι
hij : i ≠ j
n : ℤ
hnne0 : n ≠ 0
hlt : 0 < n
h1n : 1 ≤ n
⊢ a i ^ n • (X j ∪ Y j) ⊆ X i ∪ Y i

Tactic:
calc
        a i ^ n • X' j ⊆ a i ^ n • (Y i)ᶜ :=
          smul_set_mono ((hXYdisj j i).union_left <| hYdisj hij.symm).subset_compl_right
        _ ⊆ X i := by
          clear hnne0 hlt
          induction n, h1n using Int.leInduction with
          | base => rw [zpow_one]; exact hX i
          | succ n _hle hi =>
            calc
              a i ^ (n + 1) • (Y i)ᶜ = (a i ^ n * a i) • (Y i)ᶜ := by rw [zpow_add, zpow_one]
              _ = a i ^ n • a i • (Y i)ᶜ := mul_smul _ _ _
              _ ⊆ a i ^ n • X i := smul_set_mono <| hX i
              _ ⊆ a i ^ n • (Y i)ᶜ := smul_set_mono (hXYdisj i i).subset_compl_right
              _ ⊆ X i := hi
        _ ⊆ X' i := Set.subset_union_left

Goal state after:
Module: Mathlib.GroupTheory.Transfer

Goal state before:
pp: G : Type u_1
inst✝² : Group G
H : Subgroup G
A : Type u_2
inst✝¹ : CommGroup A
ϕ : ↥H →* A
S T : H.LeftTransversal
inst✝ : H.FiniteIndex
g : G
x✝¹ : Fintype (G ⧸ H) := fintypeQuotientOfFiniteIndex
x✝ : G ⧸ H
⊢ ϕ ⟨(↑(⋯.leftQuotientEquiv x✝))⁻¹ * ↑(⋯.leftQuotientEquiv x✝), ⋯⟩ =
    ϕ ⟨(↑(⋯.leftQuotientEquiv ((Equiv.symm (toPerm g)) x✝)))⁻¹ * ↑(⋯.leftQuotientEquiv ((Equiv.symm (toPerm g)) x✝)), ⋯⟩

Tactic:
simp only [smul_apply_eq_smul_apply_inv_smul, smul_eq_mul, mul_inv_rev, mul_assoc,
      inv_mul_cancel_left, toPerm_symm_apply]

Goal state after:
Module: Mathlib.GroupTheory.CoprodI

Goal state before:
pp: case h
ι : Type u_1
inst✝² : Nontrivial ι
G : Type u_1
inst✝¹ : Group G
a : ι → G
α : Type u_4
inst✝ : MulAction G α
X Y : ι → Set α
hXnonempty : ∀ (i : ι), (X i).Nonempty
hXdisj : Pairwise (Disjoint on X)
hYdisj : Pairwise (Disjoint on Y)
hXYdisj : ∀ (i j : ι), Disjoint (X i) (Y j)
hX : ∀ (i : ι), a i • (Y i)ᶜ ⊆ X i
hY : ∀ (i : ι), a⁻¹ i • (X i)ᶜ ⊆ Y i
H : ι → Type := fun _i ↦ FreeGroup Unit
f : (i : ι) → H i →* G := fun i ↦ FreeGroup.lift fun x ↦ a i
X' : ι → Set α := fun i ↦ X i ∪ Y i
inhabited_h : Inhabited ι
⊢ 3 ≤ #ℤ

Tactic:
Cardinal.mk_denumerable

Goal state after:
case h
ι : Type u_1
inst✝² : Nontrivial ι
G : Type u_1
inst✝¹ : Group G
a : ι → G
α : Type u_4
inst✝ : MulAction G α
X Y : ι → Set α
hXnonempty : ∀ (i : ι), (X i).Nonempty
hXdisj : Pairwise (Disjoint on X)
hYdisj : Pairwise (Disjoint on Y)
hXYdisj : ∀ (i j : ι), Disjoint (X i) (Y j)
hX : ∀ (i : ι), a i • (Y i)ᶜ ⊆ X i
hY : ∀ (i : ι), a⁻¹ i • (X i)ᶜ ⊆ Y i
H : ι → Type := fun _i ↦ FreeGroup Unit
f : (i : ι) → H i →* G := fun i ↦ FreeGroup.lift fun x ↦ a i
X' : ι → Set α := fun i ↦ X i ∪ Y i
inhabited_h : Inhabited ι
⊢ 3 ≤ ℵ₀
Module: Mathlib.GroupTheory.Transfer

Goal state before:
pp: case neg.inr
G : Type u_3
inst✝¹ : Group G
inst✝ : Finite G
P : Sylow (Nat.card G).minFac G
hP : IsCyclic ↥↑P
hn : ¬Nat.card G = 1
this : Fact (Nat.Prime (Nat.card G).minFac)
key : (centralizer ↑↑P).relIndex (normalizer ↑↑P) ∣ Nat.card (MulAut ↥↑P)
k : ℕ
hk : Nat.card ↥↑P = (Nat.card G).minFac ^ k
h0 : 0 < k
⊢ ((centralizer ↑P).relIndex (normalizer ↑P)).Coprime (Nat.card (MulAut ↥↑P))

Tactic:
rw [hP.card_mulAut, hk, Nat.totient_prime_pow Fact.out h0]

Goal state after:
case neg.inr
G : Type u_3
inst✝¹ : Group G
inst✝ : Finite G
P : Sylow (Nat.card G).minFac G
hP : IsCyclic ↥↑P
hn : ¬Nat.card G = 1
this : Fact (Nat.Prime (Nat.card G).minFac)
key : (centralizer ↑↑P).relIndex (normalizer ↑↑P) ∣ Nat.card (MulAut ↥↑P)
k : ℕ
hk : Nat.card ↥↑P = (Nat.card G).minFac ^ k
h0 : 0 < k
⊢ ((centralizer ↑P).relIndex (normalizer ↑P)).Coprime ((Nat.card G).minFac ^ (k - 1) * ((Nat.card G).minFac - 1))
Module: Mathlib.GroupTheory.FreeGroup.CyclicallyReduced

Goal state before:
pp: α : Type u
L : List (α × Bool)
h : IsCyclicallyReduced L
n : ℕ
⊢ IsCyclicallyReduced (replicate n L).flatten

Tactic:
by match n, L with
  | 0, _ => simp
  | n + 1, [] => simp
  | n + 1, (head :: tail) =>
    rw [isCyclicallyReduced_iff, IsReduced, List.isChain_flatten (by simp)]
    refine ⟨⟨by simpa [IsReduced] using h.isReduced, List.isChain_replicate_of_rel _ h.2⟩,
      fun _ ha _ hb ↦ ?_⟩
    rw [Option.mem_def, List.getLast?_flatten_replicate (h := by simp +arith)] at ha
    rw [Option.mem_def, List.head?_flatten_replicate (h := by simp +arith)] at hb
    exact h.2 _ ha _ hb

Goal state after:
Module: Mathlib.GroupTheory.FreeGroup.NielsenSchreier

Goal state before:
pp: G : Type u
inst✝³ : Groupoid G
inst✝² : IsFreeGroupoid G
T : WideSubquiver (Symmetrify (Generators G))
inst✝¹ : Arborescence (WideSubquiver.toType (Symmetrify (Generators G)) T)
X : Type ?u.18
inst✝ : Monoid X
f : End (root' T) →* X
X✝ Y✝ Z✝ : G
f✝ : X✝ ⟶ Y✝
g✝ : Y✝ ⟶ Z✝
⊢ f (loopOfHom T (f✝ ≫ g✝)) = f (loopOfHom T g✝) * f (loopOfHom T f✝)

Tactic:
← f.map_mul

Goal state after:
G : Type u
inst✝³ : Groupoid G
inst✝² : IsFreeGroupoid G
T : WideSubquiver (Symmetrify (Generators G))
inst✝¹ : Arborescence (WideSubquiver.toType (Symmetrify (Generators G)) T)
X : Type ?u.18
inst✝ : Monoid X
f : End (root' T) →* X
X✝ Y✝ Z✝ : G
f✝ : X✝ ⟶ Y✝
g✝ : Y✝ ⟶ Z✝
⊢ f (loopOfHom T (f✝ ≫ g✝)) = f (loopOfHom T g✝ * loopOfHom T f✝)
Module: Mathlib.GroupTheory.FreeGroup.NielsenSchreier

Goal state before:
pp: case refine_1
G : Type u
inst✝³ : Groupoid G
inst✝² : IsFreeGroupoid G
T : WideSubquiver (Symmetrify (Generators G))
inst✝¹ : Arborescence (WideSubquiver.toType (Symmetrify (Generators G)) T)
X : Type u
inst✝ : Group X
f : ↑(wideSubquiverEquivSetTotal (wideSubquiverSymmetrify T))ᶜ → X
f' : Labelling (Generators G) X :=
  fun a b e ↦ if h : e ∈ wideSubquiverSymmetrify T a b then 1 else f ⟨{ left := a, right := b, hom := e }, h⟩
F' : G ⥤ CategoryTheory.SingleObj X
hF' : ∀ (a b : Generators G) (g : a ⟶ b), F'.map (of g) = f' g
uF' :
  ∀ (y : G ⥤ CategoryTheory.SingleObj X), (fun F ↦ ∀ (a b : Generators G) (g : a ⟶ b), F.map (of g) = f' g) y → y = F'
x y : G
q : x ⟶ y
a : WideSubquiver.toType (Symmetrify (Generators G)) T
p : Path (root (WideSubquiver.toType (Symmetrify (Generators G)) T)) a
⊢ F'.map (homOfPath T p) = 1

Tactic:
induction p with
        | nil => rw [homOfPath, F'.map_id, id_as_one]
        | cons p e ih =>
          rw [homOfPath, F'.map_comp, comp_as_mul, ih, mul_one]
          rcases e with ⟨e | e, eT⟩
          · rw [hF']
            exact dif_pos (Or.inl eT)
          · rw [F'.map_inv, inv_as_inv, inv_eq_one, hF']
            exact dif_pos (Or.inr eT)

Goal state after:
Module: Mathlib.GroupTheory.SpecificGroups.Alternating

Goal state before:
pp: α : Type u_1
inst✝¹ : Fintype α
inst✝ : DecidableEq α
hα4 : 4 ≤ Nat.card α
g : Perm α
hg : g ∈ alternatingGroup α
hg' : ⟨g, hg⟩ ∈ center ↥(alternatingGroup α)
a : α
ha : a ∈ g.support
hab : g a ≠ a
c d : α
hcd : c ≠ d
hc : c ≠ a ∧ c ≠ g a
hd : d ≠ a ∧ d ≠ g a
k : Perm α := swap (g a) d * swap (g a) c
⊢ k • a = a

Tactic:
simp only [Perm.smul_def, coe_mul, Function.comp_apply, k]

Goal state after:
α : Type u_1
inst✝¹ : Fintype α
inst✝ : DecidableEq α
hα4 : 4 ≤ Nat.card α
g : Perm α
hg : g ∈ alternatingGroup α
hg' : ⟨g, hg⟩ ∈ center ↥(alternatingGroup α)
a : α
ha : a ∈ g.support
hab : g a ≠ a
c d : α
hcd : c ≠ d
hc : c ≠ a ∧ c ≠ g a
hd : d ≠ a ∧ d ≠ g a
k : Perm α := swap (g a) d * swap (g a) c
⊢ (swap (g a) d) ((swap (g a) c) a) = a
Module: Mathlib.GroupTheory.SpecificGroups.Alternating

Goal state before:
pp: case inl
α : Type u_1
inst✝¹ : Fintype α
inst✝ : DecidableEq α
G : Subgroup (Perm α)
hG : G.index ≤ 2
h : G.index = 0
⊢ alternatingGroup α ≤ G

pp: case inr
α : Type u_1
inst✝¹ : Fintype α
inst✝ : DecidableEq α
G : Subgroup (Perm α)
hG : G.index ≤ 2
h : G.index > 0
⊢ alternatingGroup α ≤ G

Tactic:
· exact (index_ne_zero_of_finite h).elim

Goal state after:
case inr
α : Type u_1
inst✝¹ : Fintype α
inst✝ : DecidableEq α
G : Subgroup (Perm α)
hG : G.index ≤ 2
h : G.index > 0
⊢ alternatingGroup α ≤ G
Module: Mathlib.GroupTheory.GroupAction.SubMulAction.OfFixingSubgroup

Goal state before:
pp: M : Type u_1
α : Type u_2
inst✝¹ : Group M
inst✝ : MulAction M α
s✝ s t : Set α
x✝¹ : ↥(fixingSubgroup M (s ∪ t))
x✝ : ↥(ofFixingSubgroup M (s ∪ t))
m : M
hm : m ∈ fixingSubgroup M (s ∪ t)
x : α
hx : x ∈ ofFixingSubgroup M (s ∪ t)
⊢ ↑↑⟨⟨↑(⟨m, hm⟩ • ⟨x, hx⟩), ⋯⟩, ⋯⟩ = ↑↑(⟨⟨↑⟨m, hm⟩, ⋯⟩, ⋯⟩ • ⟨⟨↑⟨x, hx⟩, ⋯⟩, ⋯⟩)

Tactic:
exact subgroup_smul_def ⟨m, hm⟩ x

Goal state after:
Module: Mathlib.GroupTheory.GroupAction.SubMulAction.OfFixingSubgroup

Goal state before:
pp: case inl
M : Type u_1
α : Type u_2
inst✝¹ : Group M
inst✝ : MulAction M α
s : Set α
hs : IsPretransitive ↥(fixingSubgroup M s) ↥(ofFixingSubgroup M s)
g : M
a : α
ha : a ∈ sᶜ ∩ (g • s)ᶜ
ha' : a ∈ (s ∩ g • s)ᶜ
x : α
hx✝ : x ∈ ofFixingSubgroup M (s ∩ g • s)
hx : x ∉ s
k : M
hk : k ∈ fixingSubgroup M s
hkax : ⟨k, hk⟩ • ⟨a, ⋯⟩ = ⟨x, hx⟩
⊢ ∃ g_1, g_1 • ⟨a, ha'⟩ = ⟨x, hx✝⟩

Tactic:
use ⟨k, fun ⟨y, hy⟩ ↦ hk ⟨y, hy.1⟩⟩

Goal state after:
case h
M : Type u_1
α : Type u_2
inst✝¹ : Group M
inst✝ : MulAction M α
s : Set α
hs : IsPretransitive ↥(fixingSubgroup M s) ↥(ofFixingSubgroup M s)
g : M
a : α
ha : a ∈ sᶜ ∩ (g • s)ᶜ
ha' : a ∈ (s ∩ g • s)ᶜ
x : α
hx✝ : x ∈ ofFixingSubgroup M (s ∩ g • s)
hx : x ∉ s
k : M
hk : k ∈ fixingSubgroup M s
hkax : ⟨k, hk⟩ • ⟨a, ⋯⟩ = ⟨x, hx⟩
⊢ ⟨k, ⋯⟩ • ⟨a, ha'⟩ = ⟨x, hx✝⟩
Module: Mathlib.GroupTheory.Perm.MaximalSubgroups

Goal state before:
pp: α : Type u_2
inst✝ : DecidableEq α
s : Set α
G : Subgroup (Perm α)
hG : stabilizer (Perm α) s < G
t : Set α
a b : α
ha : a ∈ t
hb : b ∈ t
h : a ≠ b
⊢ ∃ g, g.IsSwap ∧ g ∈ stabilizer (Perm α) t

Tactic:
use swap a b, Perm.swap_isSwap_iff.mpr h, swap_mem_stabilizer ha hb

Goal state after: