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The existence of a near-unanimity term in a finite algebra is decidable

Published online by Cambridge University Press:  12 March 2014

Miklós Maróti*
Affiliation:
Bolyai Institute, University of Szeged, Aradi Vértanúk Tere 1, H-6720 Szeged, Hungary, E-mail: mmaroti@math.u-szeged.hu

Abstract

We prove that it is decidable of a finite algebra whether it has a near-unanimity term operation, which settles a ten-year-old problem. As a consequence, it is decidable of a finite algebra in a congruence distributive variety whether it admits a natural duality.

Type
Research Article
Copyright
Copyright © Association for Symbolic Logic 2009

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References

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