proposition: Lemma up_form {ff : falsity_flag} xi psi : psi[↑][up xi] = psi[xi][↑].
proof: Proof. rewrite !subst_comp. apply subst_ext. reflexivity. Qed.
imports: Undecidability.Synthetic(Definitions DecidabilityFacts EnumerabilityFacts ListEnumerabilityFacts ReducibilityFacts) Undecidability(Shared.ListAutomation Shared.Dec) Coq(Eqdep_dec PeanoNat Nat) Coq.Vectors.Vector Undecidability.Shared.Libs.PSL.Vectors(Vectors) EqdepFacts