proposition: Lemma is_simple_ren_poly_type {ξ t} : is_simple (ren_poly_type ξ t) <-> is_simple t.
proof: Proof. elim t; [done | by move=> ? IH1 ? IH2 /=; rewrite IH1 IH2 | done]. 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