Partitioning complete multipartite graphs by monochromatic trees

نویسندگان

  • Atsushi Kaneko
  • Mikio Kano
  • Kazuhiro Suzuki
چکیده

The tree partition number of an r-edge-colored graph G, denoted by tr(G), is the minimum number k such that whenever the edges of G are colored with r colors, the vertices of G can be covered by at most k vertex-disjoint monochromatic trees. We determine t2(K(n1, n2, . . . , nk)) of the complete k-partite graph K(n1, n2, . . . , nk). In particular, we prove that t2(K(n,m)) = (m − 2)/2n + 2, where 1 ≤ n ≤ m.

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عنوان ژورنال:
  • Journal of Graph Theory

دوره 48  شماره 

صفحات  -

تاریخ انتشار 2005