MMN-4526
On algebras whose congruences have a class that is a subuniverse
Ivan Chajda; Helmut Länger;Abstract
We study algebras and varieties where every non-trivial congruence has some
class being a non-trivial subuniverse of the algebra in question. Then we focus on
algebras where this non-trivial class is a unique non-singleton class of the congru-
ence. In particular, we investigate Rees algebras, quasi-Rees algebras and algebras
having the one-block-property. We also present results concerning these properties on quotient algebras. Several examples of such algebras and varieties are included.
Vol. 26 (2025), No. 1, pp. 151-162