Let $R$ be a ring and $M$ a right $R$-module. $M$ is called $ \oplus $-cofinitely supplemented if every submodule $N$ of $M$ with $\frac{M}{N}$ finitely generated has a supplement that is a direct summand of $M$. In this paper various properties of the $\oplus $-cofinitely supplemented modules are given. It is shown that (1) Arbitrary direct sum of $\oplus $-cofinitely supplemented modules is $\oplus $-cofinitely supplemented. (2) A ring $R$ is semiperfect if and only if every free $R$-module is $\oplus $-cofinitely supplemented. In addition, if $M$ has the summand sum property, then $M$ is $\oplus $-cofinitely supplemented iff every maximal submodule has a supplement that is a direct summand of $M$.
Let $R$ be a ring and $M$ a right $R$-module. $M$ is called $ \oplus $-cofinitely supplemented if every submodule $N$ of $M$ with $\frac{M}{N}$ finitely generated has a supplement that is a direct summand of $M$. In this paper various properties of the $\oplus $-cofinitely supplemented modules are given. It is shown that (1) Arbitrary direct sum of $\oplus $-cofinitely supplemented modules is $\oplus $-cofinitely supplemented. (2) A ring $R$ is semiperfect if and only if every free $R$-module is $\oplus $-cofinitely supplemented. In addition, if $M$ has the summand sum property, then $M$ is $\oplus $-cofinitely supplemented iff every maximal submodule has a supplement that is a direct summand of $M$.
@article{CMJ_2004_54_4_a20,
author = {\c{C}al{\i}\c{s}{\i}c{\i}, H. and Pancar, A.},
title = {$\oplus$-cofinitely supplemented modules},
journal = {Czechoslovak Mathematical Journal},
pages = {1083--1088},
year = {2004},
volume = {54},
number = {4},
mrnumber = {2100016},
zbl = {1080.16002},
language = {en},
url = {http://geodesic.mathdoc.fr/item/CMJ_2004_54_4_a20/}
}
TY - JOUR
AU - Çalışıcı, H.
AU - Pancar, A.
TI - $\oplus$-cofinitely supplemented modules
JO - Czechoslovak Mathematical Journal
PY - 2004
SP - 1083
EP - 1088
VL - 54
IS - 4
UR - http://geodesic.mathdoc.fr/item/CMJ_2004_54_4_a20/
LA - en
ID - CMJ_2004_54_4_a20
ER -