quasi-projective covers of right $s$-acts

نویسندگان

mohammad roueentan

majid ershad

چکیده

in this paper $s$ is a monoid with a left zero and $a_s$ (or $a$) is a unitary right $s$-act. it is shown that a monoid $s$ is right perfect (semiperfect) if and only if every (finitely generated) strongly flat right $s$-act is quasi-projective. also it is shown that if every right $s$-act has a unique zero element, then the existence of a quasi-projective cover for each right act implies that every right act has a projective cover.‎

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عنوان ژورنال:
categories and general algebraic structures with applications

ناشر: shahid beheshti university

ISSN 2345-5853

دوره 2

شماره 1 2014

میزبانی شده توسط پلتفرم ابری doprax.com

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