منابع مشابه
Some counting problems related to permutation groups
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Given a digraph D, the set of all pairs (N−(v), N(v)) constitutes the neighborhood dihypergraph N (D) of D. The Digraph Realization Problem asks whether a given dihypergraph H coincides with N (D) for some digraph D. This problem was introduced by Aigner and Triesch [2] as a natural generalization of the Open Neighborhood Realization Problem for undirected graphs, which is known to be NP-comple...
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In this paper we study the parameterized complexity of two well-known permutation group problems which are NP-complete. • Given a permutation group G = 〈S〉 ≤ Sn and a parameter k, find a permutation π ∈ G such that |{i ∈ [n] | π(i) 6= i}| ≥ k. This generalizes the NP-complete problem of finding a fixed-point free permutation in G [CW10, Lub81] (this is the case when k = n). We show that this pr...
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ژورنال
عنوان ژورنال: Journal of Combinatorial Theory, Series A
سال: 1977
ISSN: 0097-3165
DOI: 10.1016/0097-3165(77)90045-0