Finitely Related Algebras in Congruence Distributive Varieties Have Near Unanimity Terms
نویسنده
چکیده
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.
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ar X iv : 0 70 5 . 22 29 v 1 [ cs . C C ] 1 5 M ay 2 00 7 On tractability and congruence distributivity ∗
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تاریخ انتشار 2011