| Title: | On left $C$-$\scr U$-liberal semigroups (English) | 
| Author: | He, Yong | 
| Author: | Shao, Fang | 
| Author: | Li, Shi-qun | 
| Author: | Gao, Wei | 
| Language: | English | 
| Journal: | Czechoslovak Mathematical Journal | 
| ISSN: | 0011-4642 (print) | 
| ISSN: | 1572-9141 (online) | 
| Volume: | 56 | 
| Issue: | 4 | 
| Year: | 2006 | 
| Pages: | 1085-1108 | 
| Summary lang: | English | 
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| Category: | math | 
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| Summary: | In this paper the equivalence  $\tilde{\mathcal Q}^U$ on a semigroup  $S$ in terms of a set  $U$ of idempotents in  $S$ is defined. A semigroup  $S$ is called a $\mathcal U$-liberal semigroup with  $U$ as the set of projections and denoted by  $S(U)$ if every $\tilde{\mathcal Q}^U$-class in it contains an element in  $U$. A class of $\mathcal U$-liberal semigroups is characterized and some special cases are considered. (English) | 
| Keyword: | equivalence $\tilde{\mathcal Q}^U$ | 
| Keyword: | left $C$-$\mathcal U$-liberal semigroup | 
| Keyword: | left semi-spined product | 
| Keyword: | band-formal construction | 
| Keyword: | left $C$-liberal semigroup | 
| MSC: | 20M10 | 
| idZBL: | Zbl 1157.20334 | 
| idMR: | MR2280796 | 
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| Date available: | 2009-09-24T11:41:22Z | 
| Last updated: | 2020-07-03 | 
| Stable URL: | http://hdl.handle.net/10338.dmlcz/128132 | 
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