proposition: Theorem fom_eq_fol_characterization x y : x ≡ y <-> x ≐ y.
proof: Proof. split; auto. Qed.
imports: List Arith Nat Lia Relations Bool Undecidability.Shared.Libs.DLW.Utils(utils_tac utils_list utils_nat finite) Undecidability.Shared.Libs.DLW.Vec(pos vec) Undecidability.FOL.TRAKHTENBROT(notations decidable gfp fol_ops fo_sig fo_terms fo_logic fo_definable fo_sat)