On Large Subsemigroups and Finiteness Conditions of Semigroups
On Large Subsemigroups and Finiteness Conditions of Semigroups
复制标题
关于大子半群和半群的有限条件
DOI:
10.1112/s0024611598000124
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发表时间:
1998
影响因子:
1.8
通讯作者:
N. Ruškuc
中科院分区:
文献类型:
--
作者:
N. Ruškuc
Let be a semigroup and let be a subsemigroup of . We say that is if the set is finite. Alternatively, we say that is a of . The cardinality of the set is called the of in , and is denoted by [ : ]. In this paper we investigate how similar a semigroup and a large subsemigroup of are. Thus, for example, it is a self-evident fact that is finite if and only if is finite. Slightly less trivially, we have the following theorem.