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, Volume 21, Issue 4, pp 333–342 | Cite as

Transformationendarstellungen endlicher abstrakt präsentierter Halbgruppen

  • H. Jürgensen
Article
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Zusammenfassung

Es wird ein halbgruppentheoretisches Analogon des Todd-Coxeter-Verfahrens in mehreren Varianten beschrieben. Der Algorithmus zählt eine Transformationendarstellung einer abstrakt präsentierten Halbgruppe auf, wobei der Kern der Darstellung durch eine durch Erzeugende gegebene Unterhalbgruppe bestimmt wird. Das Verfahren bricht genau dann ab, wenn die dabei treu dargestellte Halbgruppe endlich ist.

Transformation representations of finite abstractly presented semigroups

Summary

Several versions of an algorithm, which is an adaptation of the Todd-Coxeter-algorithm to semigroups, are described. They enumerate a representation by transformations of an abstractly presented semigroups the kernel of this representation being determined by a subsemigroup, which is given by a finite set of generators. The enumeration process stops, if and only if the semigroup faithfully represented in this manner is finite.

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Copyright information

© Springer-Verlag 1979

Authors and Affiliations

  • H. Jürgensen
    • 1
  1. 1.Institut für theoretische InformatikTechnische Hochschule DarmstadtDarmstadtBundesrepublik Deutschland

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