Quasitrivial semigroups: characterizations and enumerations
نویسندگان
چکیده
We investigate the class of quasitrivial semigroups and provide various characterizations of the subclass of quasitrivial and commutative semigroups as well as the subclass of quasitrivial and order-preserving semigroups. We also determine explicitly the sizes of these classes when the semigroups are defined on finite sets. As a byproduct of these enumerations, we obtain several new integer sequences.
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ورودعنوان ژورنال:
- CoRR
دوره abs/1709.09162 شماره
صفحات -
تاریخ انتشار 2017