fact: Definition M2 : fo_model (Σrel 2) D.
imports: Undecidability.FOL(Syntax.Facts Semantics.Tarski.FullFacts Syntax.BinSig Semantics.FiniteTarski.Full) Undecidability.FOL.TRAKHTENBROT(fo_sat fo_sig fo_terms fo_logic fol_ops) Undecidability.Synthetic.DecidabilityFacts Vector Lia