proposition: Lemma R_sn p P : R p P -> sn P.
proof: Proof. induction 1. eauto using sn. Qed.
imports: Undecidability.SystemF.SysF Undecidability.SystemF.Autosubst.syntax Undecidability.SystemF.Autosubst.unscoped Undecidability.SystemF.Util(typing_facts term_facts step) Setoid Morphisms