proposition: Lemma many_argument_app_map_argument_poly_type {P ts} : many_argument_app P (map argument_poly_type ts) = many_ty_app P ts.
proof: Proof. elim: ts P; [done | move=> /= *; by congruence]. Qed.
imports: List Lia Undecidability.SystemF.SysF Undecidability.SystemF.Autosubst.syntax Undecidability.SystemF.Autosubst.unscoped Undecidability.SystemF.Util(Facts poly_type_facts pure_term_facts) ssreflect ssrbool ssrfun