proposition: Lemma wneg_wordToN: forall sz (w: word sz), wordToN w <> 0%N -> wordToN (wneg w) = (Npow2 sz - wordToN w)%N.
proof: Proof. unfold wneg; intros. rewrite wordToN_NToWord_2. - reflexivity. - pose proof (wordToN_bound w). nomega. Qed.
imports: Coq.Classes.Morphisms Coq.Classes.Morphisms_Prop Coq.Classes.Equivalence Coq.Arith.PeanoNat Coq.ZArith.BinInt  Coq.Arith.Arith Coq.NArith.NArith Coq.Bool.Bool Coq.ZArith.ZArith Coq.Logic.Eqdep_dec Coq.Logic.EqdepFacts Coq.Program.Tactics Coq.Program.Equality Coq.setoid_ring.Ring Coq.setoid_ring.Ring_polynom bbv.Nomega bbv.ZLib bbv.NatLib bbv.NLib bbv.N_Z_nat_conversions bbv.DepEq bbv.DepEqNat bbv.ReservedNotations Coq.micromega.Lia