Theorem: Finset.Nonempty.of_mulStab (LeanCamCombi/Kneser/MulStab.lean)

State before:
ι : Type u_1
α : Type u_2
inst✝¹ : Group α
inst✝ : DecidableEq α
s t : Finset α
a : α
⊢ s.mulStab.Nonempty → s.Nonempty
Tactic:
simp_rw [nonempty_iff_ne_empty, not_imp_not]
State after:
ι : Type u_1
α : Type u_2
inst✝¹ : Group α
inst✝ : DecidableEq α
s t : Finset α
a : α
⊢ s = ∅ → s.mulStab = ∅

State before:
ι : Type u_1
α : Type u_2
inst✝¹ : Group α
inst✝ : DecidableEq α
s t : Finset α
a : α
⊢ s = ∅ → s.mulStab = ∅
Tactic:
rintro rfl
State after:
ι : Type u_1
α : Type u_2
inst✝¹ : Group α
inst✝ : DecidableEq α
t : Finset α
a : α
⊢ ∅.mulStab = ∅

State before:
ι : Type u_1
α : Type u_2
inst✝¹ : Group α
inst✝ : DecidableEq α
t : Finset α
a : α
⊢ ∅.mulStab = ∅
Tactic:
exact mulStab_empty
State after:
no goals