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[helm.git] / matita / contribs / CoRN-Decl / model / non_examples / Npos_no_monoid.ma

diff --git a/matita/contribs/CoRN-Decl/model/non_examples/Npos_no_monoid.ma b/matita/contribs/CoRN-Decl/model/non_examples/Npos_no_monoid.ma
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+(**************************************************************************)
+(*       ___                                                              *)
+(*      ||M||                                                             *)
+(*      ||A||       A project by Andrea Asperti                           *)
+(*      ||T||                                                             *)
+(*      ||I||       Developers:                                           *)
+(*      ||T||         The HELM team.                                      *)
+(*      ||A||         http://helm.cs.unibo.it                             *)
+(*      \   /                                                             *)
+(*       \ /        This file is distributed under the terms of the       *)
+(*        v         GNU General Public License Version 2                  *)
+(*                                                                        *)
+(**************************************************************************)
+
+(* This file was automatically generated: do not edit *********************)
+
+set "baseuri" "cic:/matita/CoRN-Decl/model/non_examples/Npos_no_monoid".
+
+include "CoRN.ma".
+
+(* $Id: Npos_no_monoid.v,v 1.5 2004/04/08 08:20:34 lcf Exp $ *)
+
+include "model/semigroups/Npossemigroup.ma".
+
+include "algebra/CMonoids.ma".
+
+(*#* **Non-example of a monoid: $\langle$#⟨#[Npos],[[+]]$\rangle$#⟩#
+There is no right unit for the addition on the positive natural numbers.
+*)
+
+inline "cic:/CoRN/model/non_examples/Npos_no_monoid/no_rht_unit_Npos.con".
+
+(*#* Therefore the set of positive natural numbers doesn't form a group with 
+addition.
+*)
+
+inline "cic:/CoRN/model/non_examples/Npos_no_monoid/no_monoid_Npos.con".
+