Module Zabs2Nat.
(** Results about [Z.abs_nat], converting absolute values of [Z] integers to [nat]. *)
(** [Z.abs_nat], basic equations *)
(** [Z.abs_nat] and usual operations, with non-negative integers *)

Lemma inj_pred n : 0<n -> Z.abs_nat (Z.pred n) = Nat.pred (Z.abs_nat n).