Results 11 to 20 of about 683 (105)
End-completely-regular and end-inverse lexicographic products of graphs. [PDF]
ScientificWorldJournal, 2014 A graph X is said to be End‐completely‐regular (resp., End‐inverse) if its endomorphism monoid End(X) is completely regular (resp., inverse). In this paper, we will show that if X[Y] is End‐completely‐regular (resp., End‐inverse), then both X and Y are End‐completely‐regular (resp., End‐inverse).
Hou H, Gu R.
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The Relationship between E‐Semigroups and R‐Semigroups
Journal of Mathematics, Volume 2023, Issue 1, 2023., 2023 A semigroup is called an E‐semigroup (R‐semigroup) if the set of all idempotents (the set of all regular elements) forms a subsemigroup. In this paper, we introduce the concept of V‐semigroups and establish the relationship between the three classes of semigroups.
Ze Gu, Xuanlong Ma
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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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Idempotent 2x2 matrices over linearly ordered abelian groups [PDF]
Categories and General Algebraic Structures with ApplicationsIn this paper we study multiplicative semigroups of $2\times 2$ matrices over a linearly ordered abelian group with an externally added bottom element. The multiplication of such a semigroup is defined by replacing addition and multiplication by join and
Valdis Laan, Marilyn Kutti
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Two Generalizations of Homogeneity in Groups with Applications to Regular Semigroups [PDF]
, 2014 Let $X$ be a finite set such that $|X|=n$ and let $i\leq j \leq n$. A group $G\leq \sym$ is said to be $(i,j)$-homogeneous if for every $I,J\subseteq X$, such that $|I|=i$ and $|J|=j$, there exists $g\in G$ such that $Ig\subseteq J$.
Araújo, João, Cameron, Peter J.
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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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Invariant semigroups of orthodox semigroups
Semigroup Forum, 1996 The paper is a continuation of a previous one of these authors [J. Algebra 169, No. 1, 49-70 (1994; Zbl 0811.06015)]. An inverse transversal of a regular semigroup \(S\) is an inverse subsemigroup \(T\) with the property that, for every \(x\in S\), \(T\) contains one and only one inverse element \(x^0\) of \(x\) in \(S\).
Blyth, T.S., Almeida-Santos, M.H.
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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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On generalized Ehresmann semigroups
Open Mathematics, 2017 As a generalization of the class of inverse semigroups, the class of Ehresmann semigroups is introduced by Lawson and investigated by many authors extensively in the literature.
Wang Shoufeng
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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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