proposition: Lemma BDDvar_make_preserves_nodes : forall (cfg : BDDconfig) (x : BDDvar), BDDconfig_OK cfg -> nodes_preserved cfg (fst (BDDvar_make cfg x)).
proof: Proof. intros. unfold BDDvar_make in |- *. apply BDDmake_preserves_nodes. assumption. Qed.
imports: Bool Sumbool Arith ZArith NArith Nnat Ndec Ndigits IntMap(Allmaps) Wf_nat BDDvar_ad_nat bdd1 bdd2 bdd3 bdd4 bdd5_1 bdd5_2 bdd6 bdd7 BDDdummy_lemma_2 BDDdummy_lemma_3 BDDdummy_lemma_4 bdd8 bdd9 bdd10