proposition: Fact fol_sem_ldisj_app l m φ : ⟪fol_ldisj (l++m)⟫ φ <-> ⟪fol_ldisj l⟫ φ \/ ⟪fol_ldisj m⟫ φ.
proof: Proof. rewrite !fol_sem_ldisj; split. + intros (f & H1 & H2); revert H1; rewrite in_app_iff; firstorder. + intros [ (? & ? & ?) | (? & ? & ?) ]; firstorder auto with *. Qed.
imports: List Arith Lia Undecidability.Shared.Libs.DLW.Utils(utils_tac utils_list utils_nat finite) Undecidability.Shared.Libs.DLW.Vec(pos vec) Undecidability.FOL.TRAKHTENBROT(notations utils fol_ops fo_sig fo_terms) Undecidability.Shared.ListAutomation