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ON FLATNESS COVERS OF CYCLIC ACTS OVER MONOIDS

Published online by Cambridge University Press:  09 December 2011

HUSHENG QIAO  and
LIMIN WANG
HUSHENG QIAO
Affiliation:
Department of Mathematics, Northwest Normal University Lanzhou 730070, Gansu, China e-mail: qiaohs@nwnu.edu.cn
LIMIN WANG
Affiliation:
Department of Mathematics, Northwest Normal University Lanzhou 730070, Gansu, China e-mail: qiaohs@nwnu.edu.cn
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Abstract

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The covers of cyclic acts over monoids were investigated by Mahmoudi and Renshaw (M. Mahmoudi and J. Renshaw, On covers of cyclic acts over monoids, Semigroup Forum77 (2008), 325–338) and the authors posed some open problems. In the present paper, we give answers to their problems 1 and 5, and we also give a sufficient and necessary condition that a cyclic act has a weakly pullback flat cover.

Keywords

20M30
Type
Research Article
Information
Glasgow Mathematical Journal , Volume 54 , Issue 1 , January 2012 , pp. 163 - 167
Copyright
Copyright © Glasgow Mathematical Journal Trust 2011

References

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