proposition: Lemma equiv_case_TopBot : forall e, case_TopBot↓e ⊩ (∀x, x ≡ 0 ∨ ∃y, x ≡ S y) → (⊥ → ⊤ → ⊥) ∩ (⊤ → ⊥ → ⊥).
proof: Proof. Kmove. exists 0. Ksolve. Ksolve. left. now find. do 2 Ksolve. right. find. omega. exists 1. Ksolve. Ksolve. right. find. omega. Ksolve. Kmove. destruct y. left. now find. right. find. omega. Qed.
imports: Arith Omega ClassicalRealizability.Kbase ClassicalRealizability.Integers ClassicalRealizability.KBool