Crossing Stars in Topological Graphs

نویسندگان

  • Gábor Tardos
  • Géza Tóth
چکیده

Let G be a graph without loops or multiple edges drawn in the plane. It is shown that, for any k, if G has at least Ckn edges and n vertices, then it contains three sets of k edges, such that every edge in any of the sets crosses all edges in the other two sets. Furthermore, two of the three sets can be chosen such that all k edges in the set have a common vertex.

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تاریخ انتشار 2004