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 *)
(** [Z.abs_nat] and usual operations, statements with [Z.abs] *)

Lemma inj_add_abs n m :
Z.abs_nat (Z.abs n + Z.abs m) = (Z.abs_nat n + Z.abs_nat m)%nat.