Adjoining Idempotents to Semigroups
نویسنده
چکیده
Our paper is inspired by the paper [3] by M. Nathanson, in which he considers iteration of the process of adjoining identities or zeros to semigroups and characterizes the resulting semigroup in the case when one starts with the trivial semigroup. We consider also the third type of adjoining, namely, we adjoin idempotents “that behave like some already existing elements.” We investigate the properties of the semigroups obtained by iterating these three adjoinings (in any order) in the case when one starts with the trivial semigroup. Mathematics Subject Classification: 20M14; 20M12
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