Subsemigroups of the Bicyclic Monoid
نویسندگان
چکیده
In this paper we give a description of all subsemigroups of the bicyclic monoid B. We show that there are essentially five different types of subsemigroups. One of them is the degenerate case, and the remaining four split in two groups of two, linked by the obvious anti-isomorphism of B. Each subsemigroup is characterized by a certain collection of parameters. Using our description, we determine the regular, simple and bisimple subsemigroups of B. Finally we describe algorithms for obtaining the parameters from the generating set. 2000 Mathematics Subject Classification: 20M10
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عنوان ژورنال:
- IJAC
دوره 15 شماره
صفحات -
تاریخ انتشار 2005