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arXiv · 2203.15871

Remarks on special congruences

Ivan Chajda·Helmut Länger
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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 congruence. 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.

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Ivan Chajda, Helmut Länger. 2022-03-29. Remarks on special congruences. https://arxiv.org/abs/2203.15871

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