Core-free, rank two coset geometries from edge-transitive bipartite graphs
نویسندگان
چکیده
منابع مشابه
Product of normal edge-transitive Cayley graphs
For two normal edge-transitive Cayley graphs on groups H and K which have no common direct factor and $gcd(|H/H^prime|,|Z(K)|)=1=gcd(|K/K^prime|,|Z(H)|)$, we consider four standard products of them and it is proved that only tensor product of factors can be normal edge-transitive.
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Given a bipartite graph G with n nodes, m edges and maximum degree ∆, we find an edge coloring for G using ∆ colors in time T +O(m log ∆), where T is the time needed to find a perfect matching in a k-regular bipartite graph with O(m) edges and k ≤ ∆. Together with best known bounds for T this implies an O(m log ∆ + m ∆ log m ∆ log ∆) edge-coloring algorithm which improves on the O(m log ∆+ m ∆ ...
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ژورنال
عنوان ژورنال: Mathematica Slovaca
سال: 2014
ISSN: 1337-2211,0139-9918
DOI: 10.2478/s12175-014-0253-3