Results 1 to 10 of about 93 (82)
International Journal of Mathematics and Mathematical Sciences, 1990 Let M={a,b,c,…} and Γ={α,β,γ,…} be two non-empty sets. M is called a Γ-semigroup if aαb∈M, for α∈Γ and b∈M and (aαb)βc=aα(bβc), for all a,b,c∈M and for all α,β∈Γ. A semigroup can be considered as a Γ-semigroup.
M. K. Sen, N. K. Saha
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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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International Journal of Mathematics and Mathematical Sciences, 2011 It has been well known that the band of idempotents of a naturally ordered orthodox semigroup satisfying the “strong Dubreil-Jacotin condition” forms a normal band.
Shouxu Du, Xinzhai Xu, K. P. Shum
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Journal of Algebra, 2012 Let \(S\) be a semigroup and \(\emptyset\neq B\subseteq E(S)\). Let \(\widetilde{\mathcal L}_B\) be an equivalence relation, so that for \(a,b\in S\), \(a\widetilde{\mathcal L}_Bb\) if and only if \(\{e\in B:ae=a\}=\{e\in B:be=b\}\). A semigroup \(S\) is said to be \textit{weakly B-abundant} if every \(\widetilde{\mathcal L}_B\)-class and every ...
Victoria Gould
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Identities of orthodox semigroup rings
Semigroup Forum, 1994 Let \(R\) be a ring with identity, let \(S\) be a semigroup, and let \(T\) be the subsemigroup of \(S\) generated by all idempotents of \(S\). The semigroup ring of \(S\) over \(R\) is denoted by \(R[S]\). The author is interested in the two following problems. Problem 1: when is \(R[S]\) a ring with identity? Problem 2: suppose that \(R[S]\) is a ring
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Orthodox congruences on regular semigroups
Semigroup Forum, 1988 We show that every orthodox congruence on a regular semigroup S is completely described by an orthodox congruence pair for S. A pair \((\xi,K)\) consisting of a normal congruence \(\xi\) on \(\) such that \(/\xi\) is a band and a normal subsemigroup K of S is said to be an orthodox congruence pair for S if, for all \(a,b\in S\), \(a'\in V(a)\), \(x\in \
Gracinda M S Gomes, Gomes Gracinda M S
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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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Quasi-inverse semigroup congruences on an orthodox semigroup
Semigroup Forum, 1975 Miyuki Yamada
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Some results on semigroups of transformations with restricted range
Open Mathematics, 2021 Let XX be a non-empty set and YY a non-empty subset of XX. Denote the full transformation semigroup on XX by T(X)T\left(X) and write f(X)={f(x)∣x∈X}f\left(X)=\{f\left(x)| x\in X\} for each f∈T(X)f\in T\left(X). It is well known that T(X,Y)={f∈T(X)∣f(X)⊆Y}
Yan Qingfu, Wang Shoufeng
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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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