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(*         *      The Rocq Prover / The Rocq Development Team           *)
(*  v      *         Copyright INRIA, CNRS and contributors             *)
(* <O___,, * (see version control and CREDITS file for authors & dates) *)
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(*         *     GNU Lesser General Public License Version 2.1          *)
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(** Some additional properties of [even], [odd]. *)
Module Type NParityProp (Import N : NAxiomsSig')(Import NP : NSubProp N).
Include NZParityProp N N NP.

Lemma even_sub n m : m<=n -> even (n-m) = Bool.eqb (even n) (even m).