proposition: Lemma IB_F rho : rho ⊨ F R.
proof: Proof. unfold F. rewrite !impl_sat. intros _ _ H. apply (H None). cbn. auto. Qed.
imports: Undecidability.PCP(PCP Util.PCP_facts) Undecidability.FOL(Deduction.FragmentNDFacts Semantics.Tarski.FragmentFacts Semantics.Tarski.FragmentSoundness Syntax.Core Syntax.Facts) Undecidability.FOL(FOL) Undecidability.Synthetic(Definitions DecidabilityFacts EnumerabilityFacts ReducibilityFacts MoreReducibilityFacts) Undecidability.PCP.Reductions.PCPb_iff_dPCPb Undecidability(Shared.ListAutomation)