proposition: Lemma numeral_inductive x n : hfs_inductive x -> hfs_mem (hfs_numeral n) x.
proof: Proof. intros H. induction n; cbn; apply H. apply IHn. Qed.
imports: Undecidability.FOL(Syntax.Facts Semantics.Tarski.FullFacts) Undecidability.FOL(Sets.ZF) Undecidability.FOL(ZF) Undecidability.FOL.TRAKHTENBROT(hfs) Undecidability.Shared.Libs.DLW.Utils(finite) Undecidability(Shared.ListAutomation) Lia