proposition: Lemma insert_ext' {X : Type} n i f f' (x : X) : (forall n, f n = f' n) -> insert i f x n = insert i f' x n.
proof: Proof. intro Hf. unfold insert. now destruct (Compare_dec.lt_eq_lt_dec n i) as [[?|?]|?]. Qed.
imports: PeanoNat Lia Vector Undecidability.SOL(SOL PA2) Undecidability.Shared.Libs.PSL(Vectors) Undecidability.SOL.Util(Syntax Subst Tarski) Undecidability.Synthetic(Definitions DecidabilityFacts EnumerabilityFacts ListEnumerabilityFacts ReducibilityFacts) Undecidability.Shared.Dec