on covers of acts over semigroups
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abstract
let s be a monoid and x a class of s-acts which is closed under coproducts. the object of this article is to find conditions under which all s-acts have x-precovering. we have shown that the existence of torsion-free precovering implies the existence of torsion-free covering. this work is an attempt to further facilitate the study of the conjecture that all s-acts have flat cover.
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Journal title:
iranian journal of science and technology (sciences)ISSN 1028-6276
volume 38
issue 2 2014
Keywords
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