(FUNDAMENTAL AND APPLIED MATHEMATICS)

2000, VOLUME 6, NUMBER 1, PAGES 51-61

## U-semigroups of relations

D. A. Bredikhin

Abstract

View as HTML     View as gif image    View as LaTeX source

 By a $\mathbf u$-semigroup we mean an algebra $(A,\cdot,\mathbf u)$ where $(A,\cdot)$ is a semigroup and $\mathbf u \in A$. A set of binary relations closed under the relation product and containing the universal relation $\mathbf U$ forms a $\mathbf U$-semigroup of relations which can be considered as partially ordered by inclusion. In the paper, an axiomatic description of the classes of $\mathbf U$-semigroups and partially ordered $\mathbf U$-semigroups of relations, and a basis of identities and quasiidentities of the variety and quasivariety generated by these classes are obtained. 

All articles are published in Russian.

Location: http://mech.math.msu.su/~fpm/eng/k00/k001/k00105t.htm