Results 21 to 30 of about 683 (105)
Ordered Regular Semigroups with Biggest Associates
Discussiones Mathematicae - General Algebra and Applications, 2019 We investigate the class BA of ordered regular semigroups in which each element has a biggest associate x† = max {y | xyx = x}. This class properly contains the class PO of principally ordered regular semigroups (in which there exists x⋆ = max {y | xyx ...
Blyth T.S., Santos M.H. Almeida
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Some orthodox monoids with associate inverse subsemigroups [PDF]
, 2011 By an associate inverse subsemigroup of a regular semigroup $S$ we mean a subsemigroup $T$ of $S$ containing a least associate of each $x \in S$, in relation to the natural partial order $\leq_S$ in $S$.
Billhardt, Bernd +3 more
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Elementary orthodox semigroups
Semigroup Forum, 1984 A semigroup is said to be elementary if it is generated by a subset \(A\cup B\) where \(aba=a\) and \(bab=b\) for all \(a\in A\), \(b\in B\). The authors extend their earlier work [Semigroup Forum 15, 295-309 (1978; Zbl 0403.20040)], in which free elementary orthodox semigroups were defined and their existence established, by studying the free ...
Williams, W., Eberhart, Carl
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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
wiley +1 more source
A Note on the Topology of Space-time in Special Relativity [PDF]
, 2003 We show that a topology can be defined in the four dimensional space-time of special relativity so as to obtain a topological semigroup for time. The Minkowski 4-vector character of space-time elements as well as the key properties of special relativity ...
Bohm A +5 more
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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
wiley +1 more source
Unary semigroups with an associate subgroup [PDF]
, 2008 A subgroup H of a regular semigroup S is said to be an associate subgroup of S if for every s ∈ S, there is a unique associate of s in H. An idempotent z of S is said to be medial if czc = c, for every c product of idempotents of S.
Martins, Paula Mendes, Petrich, Mario
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On quasi-F-orthodox semigroups [PDF]
Proceedings of the Edinburgh Mathematical Society, 1995 An orthodox semigroup S is termed quasi-F-orthodox if the greatest inverse semigroup homomorphic image of S1 is F-inverse. In this paper we show that each quasi-F-orthodox semigroup is embeddable into a semidirect product of a band by a group. Furthermore, we present a subclass in the class of quasi-F-orthodox semigroups whose members S are embeddable ...
Billhardt, Bernd, Szendrei, Mária B.
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Covers for regular semigroups and an application to complexity [PDF]
, 1943 A major result of D.B. McAlister for inverse semigroups is generalised in the paper to classes of regular semigroups, including the class of all regular semigroups.
Trotter, P.G.
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Special subgroups of regular semigroups [PDF]
, 2016 This work was partially supported by the Portuguese Foundation for Science and Technology through the grant UID/MAT/00297/2013 (CMA).Extending the notions of inverse transversal and associate subgroup, we consider a regular semigroup S with the property ...
Almeida Santos, M. H., Blyth, T. S.
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