Article
Keywords:
commutative; zeropotent; semigroup
Summary:
Commutative semigroups satisfying the equation $2x+y=2x$ and having only two $G$-invariant congruences for an automorphism group $G$ are considered. Some classes of these semigroups are characterized and some other examples are constructed.
References:
[2] Flaška, V., Kepka, T.:
Commutative zeropotent semigroups. Acta Univ. Carolinae 47/1 (2006), 3-14.
MR 2509893
[4] Ježek, J., Kepka, T.:
Medial groupoids. Rozpravy ČSAV, vol. 93 (1983), 93.
MR 0734873