proposition: Lemma embed_subst_t' (sigma : nat -> term') (t : term') : embed_t' t`[sigma] = (embed_t' t)`[sigma >> embed_t'].
proof: Proof. induction t; cbn; trivial. destruct F. Qed.
imports: Undecidability.FOL(Syntax.Facts Semantics.Tarski.FullFacts Deduction.FullNDFacts ZF FST) Undecidability.FOL.Sets(Models.Aczel Models.ZF_model ZF minZF FST) Undecidability.FOL.Reductions(PCPb_to_ZF PCPb_to_ZFeq PCPb_to_minZF PCPb_to_minZFeq PCPb_to_ZFD) Lia Undecidability.PCP(PCP) Undecidability(Shared.ListAutomation)