proposition: Fact Σ2_is_tuple_in_spec r n v ψ : ⟪@Σ2_is_tuple_in r n v⟫ ψ <-> mb_is_tuple_in mem (ψ r) (vec_map ψ v).
proof: Proof. simpl; fol equiv ex; intro; fol equiv conj. + rewrite Σ2_is_tuple_spec, vec_map_map; simpl; reflexivity. + reflexivity. 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)