Siberian Mathematical Journal

, Volume 46, Issue 2, pp 359–363 | Cite as

Cofinitely semiperfect modules

  • H. Calisici
  • A. Pancar


It is well known that a projective module M is ⊕-supplemented if and only if M is semiperfect. We show that a projective module M is ⊕-cofinitely supplemented if and only if M is cofinitely semiperfect or briefly cof-semiperfect (i.e., each finitely generated factor module of M has a projective cover). In this paper we give various properties of the cof-semiperfect modules. If a projective module M is semiperfect then every M-generated module is cof-semiperfect. A ring R is semiperfect if and only if every free R-module is cof-semiperfect.


semiperfect ring cofinitely submodule cofinitely semiperfect module 


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Copyright information

© Springer Science+Business Media, Inc. 2005

Authors and Affiliations

  • H. Calisici
    • 1
  • A. Pancar
    • 2
  1. 1.Ondokuz Mayis UniversityAmasyaTurkey
  2. 2.Ondokuz Mayis UniversitySamsunTurkey

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