IDEMPOTENT n-PERMUTABLE VARIETIES
نویسنده
چکیده
One of the important classes of varieties identified in tame congruence theory is the class of varieties which are n-permutable for some n. In this paper we prove two results: (1) For every n > 1 there is a polynomial-time algorithm which, given a finite idempotent algebra A in a finite language, determines whether the variety generated by A is n-permutable; (2) A variety is n-permutable for some n if and only if it interprets an idempotent variety which is not interpretable in the variety of distributive lattices.
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