proposition: Fact mb_is_pair_inj' p x y : p ≋ ⦃x,x⦄ -> p ≋ ⦃y,y⦄ -> x ≈ y.
proof: Proof. intros H1 H2; generalize (mb_is_pair_inj H1 H2); tauto. Qed.
imports: List Arith Nat Lia Max Wellfounded Coq.Setoids.Setoid Undecidability.Shared.Libs.DLW.Utils(utils_tac utils_list finite) Undecidability.Shared.Libs.DLW.Vec(pos vec) Undecidability.FOL.TRAKHTENBROT(notations fol_ops fo_sig fo_terms fo_logic)