Theorem: LO.Propositional.Classical.Formula.neg_neg (Logic/Propositional/Classical/Basic/Formula.lean)

State before:
α : Type u
α₁ : Type u₁
α₂ : Type u₂
α₃ : Type u₃
p : Formula α
⊢ p.neg.neg = p
Tactic:
induction p <;> simp[*, neg]
State after:
no goals