On generalizations of semiperfect and perfect rings
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Abstract:
We call a ring $R$ right generalized semiperfect if every simple right $R$-module is an epimorphic image of a flat right $R$-module with small kernel, that is, every simple right $R$-module has a flat $B$-cover. We give some properties of such rings along with examples. We introduce flat strong covers as flat covers which are also flat $B$-covers and give characterizations of $A$-perfect, $B$-perfect and perfect rings in terms of flat strong covers.
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Journal title
volume 42 issue 6
pages 1441- 1450
publication date 2016-12-18
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