ext n
α β α' β' : Type
γ : β → Type
x : ℕ → Bool
⊢ decrSeq x =
    propagate (fun x => true) (fun carry bits => (fun x => !bits () && carry (), _root_.xor (bits ()) (carry ())))
      fun x_1 => x
case h
α β α' β' : Type
γ : β → Type
x : ℕ → Bool
n : ℕ
⊢ decrSeq x n =
    propagate (fun x => true) (fun carry bits => (fun x => !bits () && carry (), _root_.xor (bits ()) (carry ())))
      (fun x_1 => x) n