Almeida, JorgeMoura, Ana2018-03-212018-03-212011http://hdl.handle.net/10400.22/11165The operator which constructs the pseudovariety generated by the idempotent-generated semigroups of a given pseudovariety is investigated. Several relevant examples of pseudovarieties generated by their idempotent- generated elements are given as well as some properties of this operator. Particular attention is paid to the pseudovarieties in {J, R, L, DA} concerning this operator and their generator ranks and idempotent-generator ranks.engIdempotent-generated semigroupPseudovarietyjournal article10.1017/S0013091509001795