Regular semigroup - Open Access .click

Semigroup Forum, 2004
The semigroups in this paper are defined using two kinds of generalized Green's relations defined elsewhere. A semigroup \(S\) is superabundant if each \(H^*\)-class contains an idempotent and \(S\) is semisuperabundant if both each \(\widetilde L\)- and \(\widetilde R\)-class contains at least one idempotent. A semigroup is a \(u\)-semigroup if it has
Wang, Zhengpan, Zhang, Ronghua, Xie, Mu
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Weakly regular *-semigroups

Semigroup Forum, 1999
A regular \(*\)-semigroup is a semigroup \(S\) endowed with a supplementary operation \(*\) satisfying: (1) \(xx^*=x\), for every \(x\in S\); (2) \((x^*)^*=x\), for every \(x\in S\); (3) \((xy)^*=y^*x^*\), for every \(x,y\) in \(S\). It has been proved by \textit{M.
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Congruences on *-Regular Semigroups

Periodica Mathematica Hungarica, 2002
By a *-regular semigroup \(S\) the authors mean a semigroup with involution * admitting a Moore-Penrose inverse; that is, for each \(a\in S\) there exists a (necessarily unique) solution \(x\) to the equations \(axa=a\), \(xax=x\), \((ax)^*=ax\), \((xa)^*=xa\) which is denoted by \(x=a^+\).
Crvenković, Siniša, Dolinka, Igor
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general structure theory for semigroups
regular semigroups
mathematics

inverse semigroups
idempotents
20m10

ordered semigroups and monoids
semigroup algebra
20m17