On nilpotency and residual finiteness in semigroups
Gerard J. Lallement · Pacific Journal of Mathematics · 1972
It is proved that the class c έ? of regular nilpotent semigroups coincides with the class of semilattices of nilpotent groups.Consequently, finitely generated semigroups in the class ^ are residually finite.The same results are true for semisimple 2-nilpotent semigroups.