Some congruences on eventually regular semigroups
Luo Yan-feng, Dong Yang · Journal of Lanzhou University · 2003
On any eventually regular semigroup S,the K-classes (T-classes) of some special congruences on the congruence lattice of S are studied.The K-classes with ρK being group congruence (Clifford congrence,semilattice congruence) consists of nil-extension of rectangular group congruences (semilattice of nil-extension of rectangular group congruences,semilattice of nil-extension of rectangular band congruences) on S.The T-classes with ρT being semilattice congruence (*-band congruence) consists of semilattice of nil-extension of groups congruences (*-cryptic union of nil-extension of groups congruences) on S.