ON CONATURAL CLASSES AND COTYPE SUBMODULES

Year 2012, Volume: 11 Issue: 11, 64 - 81, 01.06.2012

Alejandro Alvarado-garcía Hugo Alberto Rincón-mejía José Ríos-montes Bertha Tomé-arreola

Abstract

The concepts of cotype submodule and cotype dimension of a module are introduced, their basic properties are studied, and a characterization of the amply supplemented modules with finite cotype dimension is given.

Keywords

conatural class, cotype submodule, cotype dimension

References

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• Alejandro Alvarado-Garc´ıa, Hugo Alberto Rinc´on-Mej´ıa, Bertha Tom´e-Arreola Facultad de Ciencias Universidad Nacional Aut´onoma de M´exico Circuito Exterior, C.U. M´exico D.F. e-mails: [e-mail] (A. Alvarado) [e-mail] (H. Rinc´on) [e-mail] (B. Tom´e) Jos´e R´ıos-Montes Instituto de Matem´aticas Universidad Nacional Aut´onoma de M´exico ´ Area de la Investigaci´on Cient´ıfica Circuito Exterior, C.U. M´exico D.F. e-mail: [e-mail]