On Roots and Subsemigroups of Nilpotent Groups

Abstract

Abstract.Em Ua and Da semigroups are defined by extrapolating the definitions of their group counterparts; and a class n semigroup is defined to be a subsemigroup of a class « group. The purpose of this paper is to show that a class n Ea semigroup generates an Ea group and that a class n semigroup is Ua if and only if it generates a Ua group.