Near-Unanimity Functions and Varieties of Reflexive Graphs
نویسندگان
چکیده
منابع مشابه
Near-Unanimity Functions and Varieties of Reflexive Graphs
Let H be a graph and k ≥ 3. A near-unanimity function of arity k is a mapping g from the k-tuples over V (H) to V (H) such that g(x1, x2, . . . , xk) is adjacent to g(x ′ 1, x ′ 2, . . . , x ′ k) whenever xix ′ i ∈ E(H) for each i = 1, 2, . . . , k, and g(x1, x2, . . . , xk) = a whenever at least k − 1 of the xi’s equal a. Feder and Vardi proved that, if a graph H admits a near-unanimity functi...
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ژورنال
عنوان ژورنال: SIAM Journal on Discrete Mathematics
سال: 2008
ISSN: 0895-4801,1095-7146
DOI: 10.1137/s0895480103436748