Results 21 to 30 of about 529,491 (220)
, 2012 In this thesis we consider in detail the following two fundamental problems for semigroup presentations: 1. Given a semigroup find a presentation defining it. 2. Given a presentation describe the semigroup defined by it.
Ruškuc, Nik
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Amalgamating inverse semigroups over ample semigroups [PDF]
Proceedings of the Estonian Academy of SciencesWe consider semigroup amalgams (S; T1, T2) in which T1 and T2 are inverse semigroups and S is a non-inverse semigroup. They are known to be non-embeddable if T1 and T2 are both groups (Clifford semigroups), but S is not such. We prove that (S; T1, T2) is
Nasir Sohail
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A characterization of a ∼ admissible congruence on a weakly type B semigroup
Open Mathematics, 2023 In this article, the notions of ∼ \sim admissible congruences and ∼ \sim normal congruences on a weakly type B semigroup are characterized and the relationship between ∼ \sim admissible congruences and ∼ \sim normal congruences is investigated.
Li Chunhua +3 more
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Homogeneity of inverse semigroups [PDF]
International Journal of Algebra and Computation, 2018 An inverse semigroup [Formula: see text] is a semigroup in which every element has a unique inverse in the sense of semigroup theory, that is, if [Formula: see text] then there exists a unique [Formula: see text] such that [Formula: see text] and [Formula: see text].
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Brandt Extensions and Primitive Topological Inverse Semigroups
International Journal of Mathematics and Mathematical Sciences, 2010 We study (countably) compact and (absolutely) 𝐻-closed primitive topological inverse semigroups. We describe the structure of compact and countably compact primitive topological inverse semigroups and show that any countably compact primitive topological
Tetyana Berezovski +2 more
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Various notions of module amenability on weighted semigroup algebras
Demonstratio Mathematica, 2022 Let SS be an inverse semigroup with the set of idempotents EE. In this article, we find necessary and sufficient conditions for the weighted semigroup algebra l1(S,ω){l}^{1}\left(S,\omega ) to be module approximately amenable (contractible) and module ...
Bodaghi Abasalt, Tanha Somaye Grailoo
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Communications of the Korean Mathematical Society, 2012 Summary: \((S,*)\) is a semigroup \(S\) equipped with a unary operation ``\(*\)''. This work is devoted to a class of unary semigroups, namely \(E\)-inversive \(*\)-semigroups. A unary semigroup \((S,*)\) is called an \(E\)-inversive \(*\)-semigroup if the following identities hold: \(x^*xx^*=x^*\), \((x^*)^*=xx^*x\), \((xy)^*=y^*x^*\). In this paper, \
Wang, Shoufeng, Li, Yinghui
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Some Characterizations for Approximate Biflatness of Semigroup Algebras
Journal of Mathematics, 2023 In this paper, we study an approximate biflatness of l1S, where S is a Clifford semigroup. Indeed, we show that a Clifford semigroup algebra l1S is approximately biflat if and only if every maximal subgroup of S is amenable, ES is locally finite, and l1S
N. Razi, A. Sahami
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On generators, relations and D-simplicity of direct products, Byleen extensions, and other semigroup constructions [PDF]
, 2015 In this thesis we study two different topics, both in the context of semigroup constructions. The first is the investigation of an embedding problem, specifically the problem of whether it is possible to embed any given finitely presentable semigroup ...
Baynes, Samuel
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