mathlib-initiative/mathlib-tactics huggingface dataset:
Module: Mathlib.GroupTheory.FixedPointFree

Goal state before:
pp: F : Type u_1
G : Type u_2
inst✝³ : Group G
inst✝² : FunLike F G G
inst✝¹ : MonoidHomClass F G G
φ : F
inst✝ : Finite G
hφ : FixedPointFree ⇑φ
h2 : Function.Involutive ⇑φ
g : G
hg : orderOf g = 2
⊢ φ g = g

Tactic:
rw [hφ.coe_eq_inv_of_involutive h2, inv_eq_iff_mul_eq_one, ← sq, ← hg, pow_orderOf_eq_one]

Goal state after:
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
this✝ : ∀ᶠ (y : B) in 𝓝 x, dist (g' y) (g' x) < δ
y : B
hy : dist (g' y) (g' x) < δ
h'y : y ∈ (trivializationAt F E x).baseSet
this : ‖g' y - g' x‖ ≤ δ
v : E x
w : F := (Trivialization.continuousLinearMapAt ℝ (trivializationAt F E x) x) v
hgx : ((g x) v) v = ((g' x) w) w
⊢ ((g y) ((trivializationAt F E x).symm y w)) ((trivializationAt F E x).symm y w) ≤ r' ^ 2 * ((g x) v) v

Tactic:
have hgy : g y ((trivializationAt F E x).symm y w) ((trivializationAt F E x).symm y w)
      = g' y w w := by
    rw [inCoordinates_apply_eq₂ h'y h'y (Set.mem_univ _)]
    simp

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' : ContinuousAt g' x
this✝ : ∀ᶠ (y : B) in 𝓝 x, dist (g' y) (g' x) < δ
y : B
hy : dist (g' y) (g' x) < δ
h'y : y ∈ (trivializationAt F E x).baseSet
this : ‖g' y - g' x‖ ≤ δ
v : E x
w : F := (Trivialization.continuousLinearMapAt ℝ (trivializationAt F E x) x) v
hgx : ((g x) v) v = ((g' x) w) w
hgy : ((g y) ((trivializationAt F E x).symm y w)) ((trivializationAt F E x).symm y w) = ((g' y) w) w
⊢ ((g y) ((trivializationAt F E x).symm y w)) ((trivializationAt F E x).symm y w) ≤ r' ^ 2 * ((g x) v) v
Module: Mathlib.GroupTheory.FreeGroup.CyclicallyReduced

Goal state before:
pp: case succ
α : Type u
L : List (α × Bool)
inst✝ : DecidableEq α
h : IsReduced L
n✝ : ℕ
a✝ :
  reduce (replicate (n✝ + 1) L).flatten =
    conjugator L ++ (replicate (n✝ + 1) (reduceCyclically L)).flatten ++ invRev (conjugator L)
⊢ reduce (replicate (n✝ + 1 + 1) L).flatten =
    conjugator L ++ (replicate (n✝ + 1 + 1) (reduceCyclically L)).flatten ++ invRev (conjugator L)

Tactic:
case succ n ih =>
    rw [replicate_succ, flatten_cons, ← reduce_append_reduce_reduce, ih, h.reduce_eq]
    nth_rewrite 1 [← conj_conjugator_reduceCyclically L]
    have {L₁ L₂ L₃ L₄ L₅ : List (α × Bool)} : reduce (L₁ ++ L₂ ++ invRev L₃ ++ (L₃ ++ L₄ ++ L₅)) =
        reduce (L₁ ++ (L₂ ++ L₄) ++ L₅) := by
      apply reduce.sound
      repeat rw [← mul_mk]
      rw [← inv_mk]
      group
    rw [this, ← flatten_cons, ← replicate_succ, ← isReduced_iff_reduce_eq]
    apply IsReduced.append_flatten_replicate_append (hn := by simp)
    · exact isCyclicallyReduced h
    · rwa [conj_conjugator_reduceCyclically]

Goal state after:
Module: Mathlib.GroupTheory.Nilpotent

Goal state before:
pp: case h
G : Type u_1
inst✝ : Group G
n : ℕ
H : ℕ → Subgroup G
hH : IsAscendingCentralSeries H
hn : H n = ⊤
⊢ ⊤ ≤ upperCentralSeries G n

Tactic:
← hn

Goal state after:
case h
G : Type u_1
inst✝ : Group G
n : ℕ
H : ℕ → Subgroup G
hH : IsAscendingCentralSeries H
hn : H n = ⊤
⊢ H n ≤ upperCentralSeries G n
Module: Mathlib.GroupTheory.Nilpotent

Goal state before:
pp: G : Type u_1
inst✝ : Group G
H : ℕ → Subgroup G
n : ℕ
hn : H n = ⊥
hdesc : IsDescendingCentralSeries H
⊢ IsAscendingCentralSeries fun m ↦ H (n - m)

Tactic:
obtain ⟨h0, hH⟩ := hdesc

Goal state after:
G : Type u_1
inst✝ : Group G
H : ℕ → Subgroup G
n : ℕ
hn : H n = ⊥
h0 : H 0 = ⊤
hH : ∀ (x : G) (n : ℕ), x ∈ H n → ∀ (g : G), ⁅x, g⁆ ∈ H (n + 1)
⊢ IsAscendingCentralSeries fun m ↦ H (n - m)
Module: Mathlib.GroupTheory.FreeGroup.Orbit

Goal state before:
pp: case pos
α : Type u_1
inst✝ : DecidableEq α
w : α × Bool
g : FreeGroup α
h : g ∉ startsWith (w.1, !w.2)
hC : 0 < g.toWord.length
⊢ mk [w] * g ∈ startsWith w

Tactic:
simp only [startsWith, Set.mem_ofPred_eq, getElem?_pos, Option.some.injEq,
      Prod.eq_iff_fst_eq_snd_eq, not_and, Bool.not_eq_not, toWord_mul, toWord_mk, reduce.cons,
      reduce_nil, List.cons_append, List.nil_append, reduce_toWord, hC] at *

Goal state after:
case pos
α : Type u_1
inst✝ : DecidableEq α
w : α × Bool
g : FreeGroup α
hC✝ : 0 < g.toWord.length
h : g.toWord[0].1 = w.1 → g.toWord[0].2 = w.2
hC : True
⊢ (List.rec [w] (fun head tail tail_ih ↦ if w.1 = head.1 ∧ w.2 = !head.2 then tail else w :: head :: tail)
        g.toWord)[0]? =
    some w
Module: Mathlib.GroupTheory.FreeGroup.Orbit

Goal state before:
pp: α : Type u_1
inst✝ : DecidableEq α
w : α × Bool
g : FreeGroup α
h : g ∉ startsWith (w.1, !w.2)
⊢ mk [w] * g ∈ startsWith w

Tactic:
by
  by_cases hC : 0 < g.toWord.length
  · simp only [startsWith, Set.mem_ofPred_eq, getElem?_pos, Option.some.injEq,
      Prod.eq_iff_fst_eq_snd_eq, not_and, Bool.not_eq_not, toWord_mul, toWord_mk, reduce.cons,
      reduce_nil, List.cons_append, List.nil_append, reduce_toWord, hC] at *
    rw [show g.toWord = g.toWord.head (by grind) :: g.toWord.tail by grind]
    grind
  · simp_all [startsWith]

Goal state after:
Module: Mathlib.GroupTheory.Nilpotent

Goal state before:
pp: case refine_2
G : Type u_1
inst✝ : Group G
S : Subgroup G
n : ℕ
hn : S.lowerCentralSeries n = ⊥
⊢ ∃ n H, IsDescendingCentralSeries H ∧ H n = ⊥

Tactic:
refine ⟨n, lowerCentralSeries ⊤, lowerCentralSeries_isDescendingCentralSeries, ?_⟩

Goal state after:
case refine_2
G : Type u_1
inst✝ : Group G
S : Subgroup G
n : ℕ
hn : S.lowerCentralSeries n = ⊥
⊢ ⊤.lowerCentralSeries n = ⊥
Module: Mathlib.GroupTheory.Nilpotent

Goal state before:
pp: case refine_2
G : Type u_1
inst✝ : Group G
hG : Group.IsNilpotent G
n : ℕ
H : ℕ → Subgroup G
hH : IsAscendingCentralSeries H
hn : H n = ⊤
⊢ ⊤ ≤ upperCentralSeries G n

Tactic:
← hn

Goal state after:
case refine_2
G : Type u_1
inst✝ : Group G
hG : Group.IsNilpotent G
n : ℕ
H : ℕ → Subgroup G
hH : IsAscendingCentralSeries H
hn : H n = ⊤
⊢ H n ≤ upperCentralSeries G n
Module: Mathlib.GroupTheory.Nilpotent

Goal state before:
pp: case refine_1
G : Type u_1
inst✝ : Group G
hG : Group.IsNilpotent G
n : ℕ
H : ℕ → Subgroup G
hH : IsDescendingCentralSeries H
hn : H n = ⊥
⊢ ⊤.lowerCentralSeries n ≤ ⊥

Tactic:
← hn

Goal state after:
case refine_1
G : Type u_1
inst✝ : Group G
hG : Group.IsNilpotent G
n : ℕ
H : ℕ → Subgroup G
hH : IsDescendingCentralSeries H
hn : H n = ⊥
⊢ ⊤.lowerCentralSeries n ≤ H n
Module: Mathlib.GroupTheory.Nilpotent

Goal state before:
pp: case pos.succ.a
G : Type u_1
inst✝ : Group G
hH : IsNilpotent G
n : ℕ
hn : nilpotencyClass G = n + 1
⊢ upperCentralSeries G (n + 1) = ⊤

Tactic:
← hn

Goal state after:
case pos.succ.a
G : Type u_1
inst✝ : Group G
hH : IsNilpotent G
n : ℕ
hn : nilpotencyClass G = n + 1
⊢ upperCentralSeries G (nilpotencyClass G) = ⊤
Module: Mathlib.GroupTheory.Nilpotent

Goal state before:
pp: case neg
G : Type u_1
inst✝ : Group G
hG : ¬Group.IsNilpotent G
⊢ _root_.StrictMonoOn (upperCentralSeries G) (Set.Iic (nilpotencyClass G))

Tactic:
nilpotencyClass_of_not_nilpotent hG,

Goal state after:
case neg
G : Type u_1
inst✝ : Group G
hG : ¬Group.IsNilpotent G
⊢ _root_.StrictMonoOn (upperCentralSeries G) (Set.Iic 0)
Module: Mathlib.GroupTheory.Nilpotent

Goal state before:
pp: G₁ : Type u_2
G₂ : Type u_3
inst✝¹ : Group G₁
inst✝ : Group G₂
n : ℕ
⊢ ⊤.lowerCentralSeries n = (⊤.lowerCentralSeries n).prod (⊤.lowerCentralSeries n)

Tactic:
by
  rw [← lowerCentralSeries_prod, top_prod_top]

Goal state after:
Module: Mathlib.GroupTheory.GroupAction.Transitive

Goal state before:
pp: G : Type u_1
X : Type u_2
inst✝¹ : Group G
inst✝ : MulAction G X
a : X
⊢ IsPretransitive G X ↔ orbit G a = Set.univ

Tactic:
isPretransitive_iff_base a,

Goal state after:
G : Type u_1
X : Type u_2
inst✝¹ : Group G
inst✝ : MulAction G X
a : X
⊢ (∀ (x : X), ∃ g, g • a = x) ↔ orbit G a = Set.univ
Module: Mathlib.GroupTheory.Nilpotent

Goal state before:
pp: case h
G : Type u_1
inst✝¹ : Group G
N : Subgroup G
inst✝ : N.Normal
h : Group.IsNilpotent G
n : ℕ
hn : ⊤.lowerCentralSeries n = ⊥
⊢ derivedSeries G n ≤ ⊥

Tactic:
← hn

Goal state after:
case h
G : Type u_1
inst✝¹ : Group G
N : Subgroup G
inst✝ : N.Normal
h : Group.IsNilpotent G
n : ℕ
hn : ⊤.lowerCentralSeries n = ⊥
⊢ derivedSeries G n ≤ ⊤.lowerCentralSeries n
Module: Mathlib.GroupTheory.GroupAction.Transitive

Goal state before:
pp: M : Type u_3
N : Type u_4
α : Type u_5
β : Type u_6
inst✝³ : Monoid M
inst✝² : Monoid N
inst✝¹ : MulAction M α
inst✝ : MulAction N β
φ : M → N
f : α →ₑ[φ] β
hφ : Function.Surjective φ
hf : Function.Bijective ⇑f
⊢ IsPretransitive M α ↔ IsPretransitive N β

Tactic:
by
  constructor
  · apply IsPretransitive.of_surjective_map hf.surjective
  · intro hN
    apply IsPretransitive.mk
    intro x y
    obtain ⟨k, hk⟩ := hN.exists_smul_eq (f x) (f y)
    obtain ⟨g, rfl⟩ := hφ k
    use g
    apply hf.injective
    simp only [hk, map_smulₛₗ]

Goal state after:
Module: Mathlib.GroupTheory.GroupAction.Blocks

Goal state before:
pp: G : Type u_1
inst✝¹ : Group G
X : Type u_2
inst✝ : MulAction G X
H : Subgroup G
a : X
hH : stabilizer G a ≤ H
⊢ IsBlock G (orbit (↥H) a)

Tactic:
rw [isBlock_iff_smul_eq_of_nonempty]

Goal state after:
G : Type u_1
inst✝¹ : Group G
X : Type u_2
inst✝ : MulAction G X
H : Subgroup G
a : X
hH : stabilizer G a ≤ H
⊢ ∀ ⦃g : G⦄, (g • orbit (↥H) a ∩ orbit (↥H) a).Nonempty → g • orbit (↥H) a = orbit (↥H) a
Module: Mathlib.GroupTheory.GroupAction.Blocks

Goal state before:
pp: case inr
G : Type u_1
inst✝² : Group G
X : Type u_2
inst✝¹ : MulAction G X
inst✝ : IsPretransitive G X
B : Set X
a : X
hfB : B.Finite
B' : Set X := ⋂ k, ⋂ (_ : a ∈ k • B), k • B
hfB_ne : B.Nonempty
hB'₀ : ∀ (k : G), a ∈ k • B → B' ⊆ k • B
hfB' : B'.Finite
hag : ∀ (g : G), a ∈ g • B' → B' ⊆ g • B'
hag' : ∀ (g : G), a ∈ g • B' → B' = g • B'
⊢ IsBlock G (⋂ k, ⋂ (_ : a ∈ k • B), k • B)

Tactic:
rw [isBlock_iff_smul_eq_of_nonempty]

Goal state after:
case inr
G : Type u_1
inst✝² : Group G
X : Type u_2
inst✝¹ : MulAction G X
inst✝ : IsPretransitive G X
B : Set X
a : X
hfB : B.Finite
B' : Set X := ⋂ k, ⋂ (_ : a ∈ k • B), k • B
hfB_ne : B.Nonempty
hB'₀ : ∀ (k : G), a ∈ k • B → B' ⊆ k • B
hfB' : B'.Finite
hag : ∀ (g : G), a ∈ g • B' → B' ⊆ g • B'
hag' : ∀ (g : G), a ∈ g • B' → B' = g • B'
⊢ ∀ ⦃g : G⦄,
    ((g • ⋂ k, ⋂ (_ : a ∈ k • B), k • B) ∩ ⋂ k, ⋂ (_ : a ∈ k • B), k • B).Nonempty →
      g • ⋂ k, ⋂ (_ : a ∈ k • B), k • B = ⋂ k, ⋂ (_ : a ∈ k • B), k • B
Module: Mathlib.GroupTheory.GroupAction.Primitive

Goal state before:
pp: case mp.inl
G : Type u_3
inst✝³ : Group G
X : Type u_4
inst✝² : MulAction G X
inst✝¹ : IsPretransitive G X
inst✝ : Nontrivial X
a : X
h : IsSimpleOrder (BlockMem G a)
h_bot_or_top : ∀ (a_1 : BlockMem G a), a_1 = ⊥ ∨ a_1 = ⊤ := ⋯
B : Set X
haB : a ∈ B
hB : IsBlock G B
hB' : B = ↑⊥
⊢ B.Subsingleton

Tactic:
hB'

Goal state after:
case mp.inl
G : Type u_3
inst✝³ : Group G
X : Type u_4
inst✝² : MulAction G X
inst✝¹ : IsPretransitive G X
inst✝ : Nontrivial X
a : X
h : IsSimpleOrder (BlockMem G a)
h_bot_or_top : ∀ (a_1 : BlockMem G a), a_1 = ⊥ ∨ a_1 = ⊤ := eq_bot_or_eq_top
B : Set X
haB : a ∈ B
hB : IsBlock G B
hB' : B = ↑⊥
⊢ (↑⊥).Subsingleton
Module: Mathlib.GroupTheory.GroupAction.Primitive

Goal state before:
pp: case mp.inr
G : Type u_3
inst✝³ : Group G
X : Type u_4
inst✝² : MulAction G X
inst✝¹ : IsPretransitive G X
inst✝ : Nontrivial X
a : X
h : IsSimpleOrder (BlockMem G a)
h_bot_or_top : ∀ (a_1 : BlockMem G a), a_1 = ⊥ ∨ a_1 = ⊤ := ⋯
B : Set X
haB : a ∈ B
hB : IsBlock G B
hB' : B = ↑⊤
⊢ B = Set.univ

Tactic:
hB'

Goal state after:
case mp.inr
G : Type u_3
inst✝³ : Group G
X : Type u_4
inst✝² : MulAction G X
inst✝¹ : IsPretransitive G X
inst✝ : Nontrivial X
a : X
h : IsSimpleOrder (BlockMem G a)
h_bot_or_top : ∀ (a_1 : BlockMem G a), a_1 = ⊥ ∨ a_1 = ⊤ := eq_bot_or_eq_top
B : Set X
haB : a ∈ B
hB : IsBlock G B
hB' : B = ↑⊤
⊢ ↑⊤ = Set.univ
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
⊢ ∃ g_1, g_1 • ⟨a, ha'⟩ = ⟨x, hx✝⟩

Tactic:
obtain ⟨⟨k, hk⟩, hkax⟩ := hs.exists_smul_eq ⟨a, ha.1⟩ ⟨x, hx⟩
    use ⟨k, fun ⟨y, hy⟩ ↦ hk ⟨y, hy.1⟩⟩
    rwa [Subtype.ext_iff] at hkax ⊢

Goal state after:
Module: Mathlib.GroupTheory.GroupAction.MultiplePrimitivity

Goal state before:
pp: case right.hφ
M : Type u_1
α : Type u_2
inst✝³ : Group M
inst✝² : MulAction M α
N : Type u_3
β : Type u_4
inst✝¹ : Group N
inst✝ : MulAction N β
φ : M → N
hφ : Function.Surjective φ
f : α →ₑ[φ] β
hf : Function.Bijective ⇑f
n : ℕ
H : IsMultiplyPreprimitive N β n
s : Set α
hs : s.encard + 1 = ↑n
t : Set β := ⇑f '' s
ψ : ↥(fixingSubgroup M s) → ↥(fixingSubgroup N t) :=
  fun x ↦
    match x with
    | ⟨g, hg⟩ => ⟨φ g, ⋯⟩
g : ↥(ofFixingSubgroup M s) →ₑ[ψ] ↥(ofFixingSubgroup N t) := { toFun := fun x ↦ ⟨f ↑x, ⋯⟩, map_smul' := ⋯ }
⊢ Function.Surjective ψ

pp: case right.hf
M : Type u_1
α : Type u_2
inst✝³ : Group M
inst✝² : MulAction M α
N : Type u_3
β : Type u_4
inst✝¹ : Group N
inst✝ : MulAction N β
φ : M → N
hφ : Function.Surjective φ
f : α →ₑ[φ] β
hf : Function.Bijective ⇑f
n : ℕ
H : IsMultiplyPreprimitive N β n
s : Set α
hs : s.encard + 1 = ↑n
t : Set β := ⇑f '' s
ψ : ↥(fixingSubgroup M s) → ↥(fixingSubgroup N t) :=
  fun x ↦
    match x with
    | ⟨g, hg⟩ => ⟨φ g, ⋯⟩
g : ↥(ofFixingSubgroup M s) →ₑ[ψ] ↥(ofFixingSubgroup N t) := { toFun := fun x ↦ ⟨f ↑x, ⋯⟩, map_smul' := ⋯ }
⊢ Function.Bijective ⇑g

Tactic:
· rintro ⟨k, hk⟩
      obtain ⟨k, rfl⟩ := hφ k
      suffices k ∈ fixingSubgroup M s by
        use ⟨k, this⟩
      simp only [mem_fixingSubgroup_iff, t] at hk ⊢
      intro y hy
      apply hf.injective
      rw [map_smulₛₗ, hk]
      exact Set.mem_image_of_mem (⇑f) hy

Goal state after:
case right.hf
M : Type u_1
α : Type u_2
inst✝³ : Group M
inst✝² : MulAction M α
N : Type u_3
β : Type u_4
inst✝¹ : Group N
inst✝ : MulAction N β
φ : M → N
hφ : Function.Surjective φ
f : α →ₑ[φ] β
hf : Function.Bijective ⇑f
n : ℕ
H : IsMultiplyPreprimitive N β n
s : Set α
hs : s.encard + 1 = ↑n
t : Set β := ⇑f '' s
ψ : ↥(fixingSubgroup M s) → ↥(fixingSubgroup N t) :=
  fun x ↦
    match x with
    | ⟨g, hg⟩ => ⟨φ g, ⋯⟩
g : ↥(ofFixingSubgroup M s) →ₑ[ψ] ↥(ofFixingSubgroup N t) := { toFun := fun x ↦ ⟨f ↑x, ⋯⟩, map_smul' := ⋯ }
⊢ Function.Bijective ⇑g
Module: Mathlib.GroupTheory.Perm.MaximalSubgroups

Goal state before:
pp: M : Type u_1
α : Type u_2
inst✝² : Group M
inst✝¹ : MulAction M α
B : Set α
G : Subgroup M
hB : IsBlock (↥G) B
inst✝ : IsPreprimitive ↥(stabilizer (↥G) B) ↑B
hB_not_le_sc : ∀ (B_1 : Set α), IsBlock (↥G) B_1 → B_1 ⊆ Bᶜ → B_1.Subsingleton
hG : stabilizer M B < G
hBs : B ⊆ B
hB' : Subtype.val ⁻¹' B = Set.univ
g' : M
hg' : g' ∈ G
hg's : g' ∉ stabilizer M B
h : _root_.Disjoint (⟨g', hg'⟩ • B) B
this : (g' • B).Subsingleton
⊢ B.Subsingleton

Tactic:
by
        exact subsingleton_of_image (MulAction.injective g') B this

Goal state after:
Module: Mathlib.GroupTheory.GroupAction.Jordan

Goal state before:
pp: case succ
n : ℕ
hrec :
  ∀ {G : Type u_1} {α : Type u_2} [inst : Group G] [inst_1 : MulAction G α],
    IsPreprimitive G α →
      ∀ {s : Set α},
        s.ncard = n + 1 →
          n + 2 < Nat.card α →
            IsPreprimitive ↥(fixingSubgroup G s) ↥(ofFixingSubgroup G s) → Finite α → IsMultiplyPreprimitive G α (n + 2)
G : Type u_1
α : Type u_2
inst✝¹ : Group G
inst✝ : MulAction G α
hG : IsPreprimitive G α
s : Set α
hsn : s.ncard = n + 1 + 1
hsn' : n + 1 + 2 < Nat.card α
hprim : IsPreprimitive ↥(fixingSubgroup G s) ↥(ofFixingSubgroup G s)
hα : Finite α
⊢ s.Nonempty

Tactic:
rw [← Set.ncard_pos, hsn]

Goal state after:
case succ
n : ℕ
hrec :
  ∀ {G : Type u_1} {α : Type u_2} [inst : Group G] [inst_1 : MulAction G α],
    IsPreprimitive G α →
      ∀ {s : Set α},
        s.ncard = n + 1 →
          n + 2 < Nat.card α →
            IsPreprimitive ↥(fixingSubgroup G s) ↥(ofFixingSubgroup G s) → Finite α → IsMultiplyPreprimitive G α (n + 2)
G : Type u_1
α : Type u_2
inst✝¹ : Group G
inst✝ : MulAction G α
hG : IsPreprimitive G α
s : Set α
hsn : s.ncard = n + 1 + 1
hsn' : n + 1 + 2 < Nat.card α
hprim : IsPreprimitive ↥(fixingSubgroup G s) ↥(ofFixingSubgroup G s)
hα : Finite α
⊢ 0 < n + 1 + 1
Module: Mathlib.GroupTheory.GroupExtension.Basic

Goal state before:
pp: N : Type u_1
G : Type u_2
inst✝³ : Group N
inst✝² : Group G
E : Type u_3
inst✝¹ : Group E
S : GroupExtension N E G
E' : Type u_4
inst✝ : Group E'
S' : GroupExtension N E' G
f : E →* E'
comp_inl : f.comp S.inl = S'.inl
rightHom_comp : S'.rightHom.comp f = S.rightHom
e : E
⊢ (fun e' ↦
        let e := Function.surjInv ⋯ (S'.rightHom e');
        e * S.inl (Function.invFun (⇑S'.inl) ((f e)⁻¹ * e')))
      ((↑f).toFun e) =
    e

Tactic:
by
    simp only [OneHom.toFun_eq_coe, MonoidHom.toOneHom_coe, ← map_inv, ← map_mul]
    obtain ⟨n, hn⟩ :
        (Function.surjInv S.rightHom_surjective (S'.rightHom (f e)))⁻¹ * e ∈ S.inl.range := by
      rw [S.range_inl_eq_ker_rightHom, MonoidHom.mem_ker, map_mul, map_inv, ← MonoidHom.comp_apply,
        rightHom_comp]
      simpa only [Function.surjInv_eq] using inv_mul_cancel (S.rightHom e)
    rw [← eq_inv_mul_iff_mul_eq, ← hn, ← MonoidHom.comp_apply, comp_inl,
      Function.leftInverse_invFun S'.inl_injective]

Goal state after:
Module: Mathlib.GroupTheory.GroupAction.Jordan

Goal state before:
pp: α : Type u_1
G : Subgroup (Perm α)
inst✝¹ : Fintype α
inst✝ : DecidableEq α
hG : IsPreprimitive (↥G) α
g : Perm α
h3g : g.IsThreeCycle
hg : g ∈ G
hα4 : Nat.card α ≥ 4
n : ℕ
hn : Nat.card α = n + 4
this : IsPretransitive ↥(fixingSubgroup (↥G) (↑g.support)ᶜ) ↥(ofFixingSubgroup (↥G) (↑g.support)ᶜ)
⊢ Nat.card ↥(ofFixingSubgroup (↥G) (↑g.support)ᶜ) = 3

Tactic:
rw [Nat.card_eq_fintype_card, Fintype.card_subtype, ← h3g.card_support]

Goal state after:
α : Type u_1
G : Subgroup (Perm α)
inst✝¹ : Fintype α
inst✝ : DecidableEq α
hG : IsPreprimitive (↥G) α
g : Perm α
h3g : g.IsThreeCycle
hg : g ∈ G
hα4 : Nat.card α ≥ 4
n : ℕ
hn : Nat.card α = n + 4
this : IsPretransitive ↥(fixingSubgroup (↥G) (↑g.support)ᶜ) ↥(ofFixingSubgroup (↥G) (↑g.support)ᶜ)
⊢ {x | x ∈ ofFixingSubgroup (↥G) (↑g.support)ᶜ}.card = g.support.card
Module: Mathlib.GroupTheory.MonoidLocalization.UniqueFactorization

Goal state before:
pp: case h.refine_1
M : Type u_1
N : Type u_2
inst✝² : CommMonoidWithZero M
inst✝¹ : CommMonoidWithZero N
S : Submonoid M
f : S.LocalizationMap N
inst✝ : UniqueFactorizationMonoid M
this : IsCancelMulZero N
n : N
m : M
s : ↥S
hn : ¬f (m, s).1 = 0
eq : n * f ↑(m, s).2 = f (m, s).1
x : N
hx : x ∈ Multiset.filter (fun x ↦ ¬IsUnit x) (Multiset.map (⇑f) (factors m))
⊢ Prime x

Tactic:
rw [Multiset.mem_filter, Multiset.mem_map] at hx

Goal state after:
case h.refine_1
M : Type u_1
N : Type u_2
inst✝² : CommMonoidWithZero M
inst✝¹ : CommMonoidWithZero N
S : Submonoid M
f : S.LocalizationMap N
inst✝ : UniqueFactorizationMonoid M
this : IsCancelMulZero N
n : N
m : M
s : ↥S
hn : ¬f (m, s).1 = 0
eq : n * f ↑(m, s).2 = f (m, s).1
x : N
hx : (∃ a ∈ factors m, f a = x) ∧ ¬IsUnit x
⊢ Prime x
Module: Mathlib.GroupTheory.Perm.Cycle.PossibleTypes

Goal state before:
pp: case h.right.right.hf
α : Type u_2
inst✝ : Fintype α
c : List ℕ
hc : c.sum ≤ Fintype.card α
klift : (n : ℕ) → n < Fintype.card α → Fin (Fintype.card α) := fun n hn ↦ ⟨n, hn⟩
klift' : (l : List ℕ) → (∀ a ∈ l, a < Fintype.card α) → List (Fin (Fintype.card α)) := fun l hl ↦ pmap klift l hl
hc'_lt : ∀ l ∈ c.ranges, ∀ n ∈ l, n < Fintype.card α
l : List (List (Fin (Fintype.card α))) := pmap klift' c.ranges hc'_lt
hl : ∀ (a : List ℕ) (ha : a ∈ c.ranges), map (⇑Fin.valEmbedding) (klift' a ⋯) = a
u : List ℕ
hu : ∀ a ∈ u, a < Fintype.card α
v : List ℕ
hv : ∀ a ∈ v, a < Fintype.card α
huv : u.Disjoint v
a : ℕ
⊢ ∀ (a' : ℕ) (ha : a < Fintype.card α) (ha' : a' < Fintype.card α), klift a ha = klift a' ha' → a = a'

Tactic:
a'

Goal state after:
case h.right.right.hf
α : Type u_2
inst✝ : Fintype α
c : List ℕ
hc : c.sum ≤ Fintype.card α
klift : (n : ℕ) → n < Fintype.card α → Fin (Fintype.card α) := fun n hn ↦ ⟨n, hn⟩
klift' : (l : List ℕ) → (∀ a ∈ l, a < Fintype.card α) → List (Fin (Fintype.card α)) := fun l hl ↦ pmap klift l hl
hc'_lt : ∀ l ∈ c.ranges, ∀ n ∈ l, n < Fintype.card α
l : List (List (Fin (Fintype.card α))) := pmap klift' c.ranges hc'_lt
hl : ∀ (a : List ℕ) (ha : a ∈ c.ranges), map (⇑Fin.valEmbedding) (klift' a ⋯) = a
u : List ℕ
hu : ∀ a ∈ u, a < Fintype.card α
v : List ℕ
hv : ∀ a ∈ v, a < Fintype.card α
huv : u.Disjoint v
a a' : ℕ
⊢ ∀ (ha : a < Fintype.card α) (ha' : a' < Fintype.card α), klift a ha = klift a' ha' → a = a'
Module: Mathlib.GroupTheory.HNNExtension

Goal state before:
pp: case neg.e_g
G : Type u_1
inst✝ : Group G
A B : Subgroup G
φ : ↥A ≃* ↥B
d : TransversalPair G A B
g : ↥A
w : NormalWord d
this : Cancels 1 (↑g • w) ↔ Cancels 1 w
hcan : ¬Cancels 1 w
⊢ ↑(φ (g * (⋯.equiv w.head).1)) = ↑(φ g) * ↑(φ (⋯.equiv w.head).1)

Tactic:
simp only [SetLike.coe_sort_coe, map_mul, Subgroup.coe_mul]

Goal state after:
Module: Mathlib.GroupTheory.Perm.ClosureSwap

Goal state before:
pp: case refine_2
α : Type u_2
inst✝ : DecidableEq α
S : Set (Equiv.Perm α)
hS : ∀ f ∈ S, f.IsSwap
f : Equiv.Perm α
hf : ∀ (x : α), f x ∈ orbit (↥(closure S)) x
supp : Set α := (fixedBy α f)ᶜ
fin : supp.Finite
supp_eq : supp = (fixedBy α f)ᶜ
⊢ f ∈ closure S

Tactic:
suffices h : (fixedBy α f)ᶜ ⊆ supp → f ∈ closure S from h supp_eq.symm.subset

Goal state after:
case refine_2
α : Type u_2
inst✝ : DecidableEq α
S : Set (Equiv.Perm α)
hS : ∀ f ∈ S, f.IsSwap
f : Equiv.Perm α
hf : ∀ (x : α), f x ∈ orbit (↥(closure S)) x
supp : Set α := (fixedBy α f)ᶜ
fin : supp.Finite
supp_eq : supp = (fixedBy α f)ᶜ
⊢ (fixedBy α f)ᶜ ⊆ supp → f ∈ closure S
Module: Mathlib.GroupTheory.Perm.Centralizer

Goal state before:
pp: case pos
α : Type u_1
inst✝¹ : DecidableEq α
inst✝ : Fintype α
g : Perm α
a : g.Basis
τ : ↥(range_toPermHom' g)
x : α
c : ↥g.cycleFactorsFinset
hc : x ∈ (↑c).support
m : ℤ
hm : (g ^ m) (a c) = x
H : ↑τ c = c
⊢ ∀ (a : ↥g.cycleFactorsFinset), ↑τ a ≠ a → ↑a x = x

Tactic:
intro d hd

Goal state after:
case pos
α : Type u_1
inst✝¹ : DecidableEq α
inst✝ : Fintype α
g : Perm α
a : g.Basis
τ : ↥(range_toPermHom' g)
x : α
c : ↥g.cycleFactorsFinset
hc : x ∈ (↑c).support
m : ℤ
hm : (g ^ m) (a c) = x
H : ↑τ c = c
d : ↥g.cycleFactorsFinset
hd : ↑τ d ≠ d
⊢ ↑d x = x