An element $e$ of an ordered semigroup S is called an ordered idempotent if e ≤ e². Here we characterize the subsemigroup $<E_{≤}(S)>$ generated by the set of all ordered idempotents of a regular ordered semigroup S. If S is a regular ordered semigroup then $<E_{≤}(S)>$ is also regular. If S is a regular ordered semigroup generated by its ordered idempotents then every ideal of S is generated as a subsemigroup by ordered idempotents.
Department of Mathematics, Visva-Bharati, Santiniketan - 731235, India
Bibliografia
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