proposition: Lemma pure_typing_many_poly_abs_contains_closed {s t t' n} : allfv_poly_type (fun=> False) s -> contains (many_poly_abs n t) t' -> pure_typing [s] (pure_var 0) t -> pure_typing [s] (pure_var 0) t'.
proof: Proof. by move=> /pure_typing_many_poly_abs_closed H /pure_typing_contains HC /H => /(_ n) /HC. Qed.
imports: List Lia Relation_Definitions Relation_Operators Operators_Properties Undecidability.SystemF.SysF Undecidability.SystemF.Autosubst.syntax Undecidability.SystemF.Autosubst.unscoped Undecidability.SystemF.Util(Facts poly_type_facts pure_term_facts term_facts typing_facts iipc2_facts) ssreflect ssrbool ssrfun