cujse Cankaya University Journal of Science and Engineering 2564-7954 Cankaya University Engineering Mühendislik W-Coatomic Modules Bilhan Gökhan Güroğlu Tuğba 02 01 2010 7 1 05 13 2010 Copyright © 2009, Cankaya University Journal of Science and Engineering 2009 Cankaya University Journal of Science and Engineering

In this paper we introduce w-coatomic modules and some of their properties.We prove that the finite sum of w-coatomic modules is w-coatomic. It is shown thatw-coatomic modules are closed under extensions. It is proved that if an R-module M isreduced and every proper semisimple submodule N of M has a supplement in M, then Mis w-coatomic.

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