Maximal groups in sandwich semigroups of binary relations

Karen Chase

Vol. 100 (1982), No. 1, 43–59

DOI: 10.2140/pjm.1982.100.43

Abstract

A sandwich semigroup is given as follows. Let R be an arbitrary but fixed binary relation on a finite set X. For relations A and B on X we say (a,b) ∈ A∗B (the product of A and B) if there are c and d in X such that (a,c) ∈ A, (c,d) ∈ R and (d,b) ∈ B. This semigroup is denoted B_X(R). In this paper we study maximal groups in B_X(R) for various classes of R.

Mathematical Subject Classification 2000

Primary: 20M10

Secondary: 04A05

Milestones

Received: 25 August 1980

Published: 1 May 1982