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Discussiones Mathematicae General Algebra and Applications 20(1) (2000) 63-75
DOI: https://doi.org/10.7151/dmgaa.1006

STRUCTURE THEOREMS FOR RIGHT pp-SEMI-GROUPS WITH LEFT CENTRAL IDEMPOTENTS

Xue Ming Ren and Kar-Ping Shum

Department of Mathematics, The Chinese University of Hong Kong
Shatin, N.T., Hong Kong

Abstract

The concept of strong spined product of semigroups is introduced. We first show that a semigroup S is a rpp-semigroup with left central idempotents if and only if S is a strong semilattice of left cancellative right stripes. Then, we show that such kind of semigroups can be described by the strong spined product of a C-rpp-semigroup and a right normal band. In particular, we show that a semigroup is a rpp-semigroup with left central idempotents if and only if it is a right bin.

Keywords: right pp-semigroups; right zero bands; strong spined products.

1991 Mathematics Subject Classification: 20M10.

References

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Received 29 August 1998
Revised 15 June 1999
Revised 25 February 2000