Results 51 to 60 of about 468 (134)
Ideals and finiteness conditions for subsemigroups
, 2013 In this paper we consider a number of finiteness conditions for semigroups related to their ideal structure, and ask whether such conditions are preserved by sub- or supersemigroups with finite Rees or Green index. Specific properties under consideration
Ruskuc, N. +7 more
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Compact semitopological inverse Clifford Semigroups
Semigroup Forum, 1972 An inverse Clifford Semigroup is a semilattice of groups. Conditions are given for constructing a compact semitopological (separately continuous multiplication) inverse Clifford semigroup on a compact Hausdorff semilattice. The conditions are necessary and sufficient for decomposing a compact inverse Clifford semigroup containing a dense subgroup and ...
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Green index and finiteness conditions for semigroups
, 2008 Let S be a semigroup and let T be a subsemigroup of S. Then T acts on S by left and by right multiplication. If the complement S \ T has finitely many strong orbits by both these actions we say that T has finite Green index in S.
R. Gray +7 more
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On positive definite functions and representations of Clifford ω-semigroups
Le Matematiche, 1995 It is known that a complex valued function f on a Clifford ω-semigroup, T=UnGn is positive definite if and only if its restriction fn to Gn, is positive definite for any positive integer n.
Liliana Pavel
doaj
On positive definite functions and representation of Clifford ω-semigroups
Le Matematiche, 1995 errata corrige.
Liliana Pavel
doaj
On inverse semigroups the closure of whose set of idempotents is a clifford semigroup
Semigroup Forum, 1992 The semigroups mentioned in the title \{they form the first uninvestigated class in the \textit{M. Petrich} and \textit{N. R. Reilly} diagram [Trans. Am. Math. Soc. 270, 309-325 (1982; Zbl 0484.20026)]\} are exactly the inverse subsemigroups of semidirect products of a Clifford semigroup and a group. Under an additional condition \textit{D.
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Semigroups of order-decreasing transformations
, 2012 Let X be a totally ordered set and consider the semigroups of orderdecreasing (increasing) full (partial, partial one-to-one) transformations of X. In this Thesis the study of order-increasing full (partial, partial one-to-one) transformations has been
Umar, Abdullahi
core
A structure theorem for completely regular semigroups
, 1987 Structure theorems for arbitrary completely regular semigroups have been given by Yamada, Warne, Petrich, and Clifford. A new structure theorem for these semigroups is proved here.
Mario Petrich
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Invariants for E_0-semigroups on II_1 factors [PDF]
, 2013 We introduce four new cocycle conjugacy invariants for $E_0$-semigroups on II$_1$ factors: a coupling index, a dimension for the gauge group, a \emph{super product system} and a $C^*$-semiflow.
R. Srinivasan +3 more
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The semigroup generated by certain operators on the congruence lattice of a clifford semigroup
Semigroup Forum, 1992 For any congruence relation \(\rho\) on a regular semigroup \(S\), let \(\rho K\) and \(\rho k\) be the greatest and the least congruences on \(S\) with the same kernel as \(\rho\), and, \(\rho T\) and \(\rho t\) the greatest and the least congruences on \(S\) with the same trace as \(\rho\). The semigroup generated by the set \(\Gamma=\{k,K,t,T\}\) of
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