Results 21 to 30 of about 89 (75)
HOMOGENEOUS COMPLETELY SIMPLE SEMIGROUPS
Mathematika, Volume 66, Issue 3, Page 733-751, July 2020., 2020 Abstract A semigroup is completely simple if it has no proper ideals and contains a primitive idempotent. We say that a completely simple semigroup S is a homogeneous completely simple semigroup if any isomorphism between finitely generated completely simple sub‐semigroups of S extends to an automorphism of S.
Thomas Quinn‐Gregson
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Unit orthodox semigroups [PDF]
Glasgow Mathematical Journal, 1983 Let S be a regular semigroup. Given x ∈ S, we shall say that a ∈ S is an associate of x if xax = x. The set of associates of x ∈ S will be denoted by A(x). Now suppose that S has an identity element 1. Let H1 denote the group of units of S. Then we say that u ∈ S is a unit associate of x whenever u ∈ A(x)∩Hl. In what follows we shall write U(x) = A(x)∩=
Blyth, T. S., McFadden, R.
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Congruences on Orthodox Semigroups [PDF]
Journal of the Australian Mathematical Society, 1971 A semigroup S is called regular if a ∈ aSa for every element a in S. The elementary properties of regular semigroups may be found in A. H. Clifford and G. B. Preston [1]. A semigroup S is called orthodox if S is regular and if the idempotents of S form a subsemigroup of S.
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Flows on Classes of Regular Semigroups and Cauchy Categories
Journal of Mathematics, Volume 2019, Issue 1, 2019., 2019 We consider the structure of the flow monoid for some classes of regular semigroups (which are special case of flows on categories) and for Cauchy categories. In detail, we characterize flows for Rees matrix semigroups, rectangular bands, and full transformation semigroups and also describe the Cauchy categories for some classes of regular semigroups ...
Suha Ahmed Wazzan, Radomír Halaš
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Characterizations of N(2,2, 0) Algebras
Algebra, Volume 2016, Issue 1, 2016., 2016 The so‐called ideal and subalgebra and some additional concepts of N(2, 2, 0) algebras are discussed. A partial order and congruence relations on N(2, 2, 0) algebras are also proposed, and some properties are investigated.
Fang-an Deng +4 more
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International Journal of Mathematics and Mathematical Sciences, Volume 30, Issue 8, Page 459-466, 2002., 2002 Let R be a ring. The circle operation is the operation a∘b = a + b − ab, for all a, b ∈ R. This operation gives rise to a semigroup called the adjoint semigroup or circle semigroup of R. We investigate rings in which the adjoint semigroup is regular. Examples are given which illustrate and delimit the theory developed.
Henry E. Heatherly, Ralph P. Tucci
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Γ‐group congruences on regular Γ‐semigroups
International Journal of Mathematics and Mathematical Sciences, Volume 15, Issue 1, Page 103-106, 1992., 1990 In this paper a Γ‐group congruence on a regular Γ‐semigroup is defined, some equivalent expressions for any Γ‐group congruence on a regular Γ‐semigroup and those for the least Γ‐group congruence in particular are given.
A. Seth
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On the diameter of semigroups of transformations and partitions
Journal of the London Mathematical Society, Volume 110, Issue 1, July 2024.Abstract For a semigroup S$S$ whose universal right congruence is finitely generated (or, equivalently, a semigroup satisfying the homological finiteness property of being type right‐FP1$FP_1$), the right diameter of S$S$ is a parameter that expresses how ‘far apart’ elements of S$S$ can be from each other, in a certain sense.
James East +4 more
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Quasi-abelian and quasi-solvable regular semigroups
Le Matematiche, 1996 In this note quasi-abelian semigroups are studied and it is proved that they form an e-variety of orthodox semigroups. More, quasi-abelian regular Bruck-Reilly monoids are characterized as extensions of monoids which are (reverse) semidirect products of ...
Brunetto Piochi
doaj
On orthodox semigroups determined by their bundles of correspondences [PDF]
Pacific Journal of Mathematics, 1992 It is known that the set \({\mathcal C}(S)\) of all correspondences of any given algebra \(S\) (i.e. stable binary relations on \(S\)) forms a partially ordered semigroup with involution with respect to the partial order ``\(\subseteq\)'', the composition ``\(\circ\)'' and the unary operation ``\(^{-1}\)''.
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