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(*         *   The Coq Proof Assistant / The Coq Development Team       *)
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(* <O___,, *       (see CREDITS file for the list of authors)           *)
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(*    //   *    This file is distributed under the terms of the         *)
(*         *     GNU Lesser General Public License Version 2.1          *)
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Local Open Scope R_scope.

Lemma Rsum_abs :
forall (An:nat -> R) (N:nat),
Rabs (sum_f_R0 An N) <= sum_f_R0 (fun l:nat => Rabs (An l)) N.