Few subpowers, congruence distributivity and near-unanimity terms
نویسندگان
چکیده
We prove that for any variety V, the existence of an edge-term (defined in [1]) and Jónsson terms is equivalent to the existence of a near-unanimity term. We also characterize the idempotent Maltsev conditions which are defined by a system of linear absorption equations and which imply congruence distributivity.
منابع مشابه
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 ∗
Constraint languages that arise from finite algebras have recently been the object of study, especially in connection with the Dichotomy Conjecture of Feder and Vardi. An important class of algebras are those that generate congruence distributive varieties and included among this class are lattices, and more generally, those algebras that have near-unanimity term operations. An algebra will gen...
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