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Finitely Related Algebras in CongruenceDistributive Varieties Have Near UnanimityTerms

Published online by Cambridge University Press:  20 November 2018

Libor Barto*
Affiliation:
Department of Mathematics and Statistics, McMaster University, Hamilton, ON
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Abstract

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We show that every finite, finitely related algebra in a congruence distributive variety has a near unanimity term operation. As a consequence we solve the near unanimity problem for relational structures: it is decidable whether a given finite set of relations on a finite set admits a compatible near unanimity operation. This consequence also implies that it is decidable whether a given finite constraint language defines a constraint satisfaction problem of bounded strict width.

Type
Research Article
Copyright
Copyright © Canadian Mathematical Society 2013

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