fact: Definition P_W : term := app (ty_app (ty_app (var 0) (poly_var 0)) t_x_W) Q_W.
imports: List Lia Undecidability.SystemF.SysF Undecidability.SystemF.Autosubst.syntax Undecidability.SystemF.Util(Facts poly_type_facts pure_term_facts term_facts typing_facts pure_typing_facts pure_typable_prenex) ssreflect ssrbool ssrfun