Bounded relational width
نویسنده
چکیده
We prove that CSP(A) for an idempotent algebra A has bounded relational width if and only if var(A) omits the unary and affine types. If it has bounded relational width it has relational width at most 3. The problem, given a relational structure A, decide if CSP(A) has bounded relational width (equivalently, if the variety generated by the corresponding algebra omits the Boolean and affine types) is polynomial time.
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تاریخ انتشار 2009