proposition: Lemma up_term (t : term) xi : t`[↑]`[up xi] = t`[xi]`[↑].
proof: Proof. rewrite !subst_term_comp. apply subst_term_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