ArticleOriginal scientific text
Title
Modyfications of Csákány's Theorem
Authors 1
Affiliations
- Department of Algebra and Geometry, Palacký University of Olomouc, Tomkova 40, Cz-779 00 Olomouc, Czech Republic
Abstract
Varieties whose algebras have no idempotent element were characterized by B. Csákány by the property that no proper subalgebra of an algebra of such a variety is a congruence class. We simplify this result for permutable varieties and we give a local version of the theorem for varieties with nullary operations.
Keywords
congruence class, idempotent element, permutable variety, Mal'cev condition
Bibliography
- I. Chajda and J. Duda, Compact universal relation in varieties with constants, Czechoslovak Math. J. 47 (1997), 173-178.
- B. Csákány, Varieties whose algebras have no idempotent elements, Colloq. Math. 35 (1976), 201-203.
- J. Kollár, Congruences and one-element subalgebras, Algebra Universalis 9 (1979), 266-267.