Affiliation:
1. Department of Mathematics, Nanjing Forestry University, Nanjing, 210037, P.R. China
Abstract
Abstract
An ordered monoid S in which every principal left ideal, regarded as an S-poset, is projective is called an ordered left PP monoid, for short, an ordered lpp monoid. In this paper, we introduce a new kind of ordered relations instead of Green relations adopted by J. B. Fountain, ordered lpp monoids are described by these ordered relations. Some similar results of c-rpp semigroups are duduced and proved, in particular, Fountain’s results about C-lpp monoids are generalized to ordered monoids.