Theorem: Finset.mulStab_singleton (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✝ a : α
⊢ {a}.mulStab = 1
Tactic:
simp [mulStab, singleton_one, filter_true_of_mem]
State after:
no goals