Packing edge-disjoint triangles in regular and almost regular tournaments

نویسندگان

  • Islam Akaria
  • Raphael Yuster
چکیده

For a tournament T , let ν3(T ) denote the maximum number of pairwise edge-disjoint triangles (directed cycles of length 3) in T . Let ν3(n) denote the minimum of ν3(T ) ranging over all regular tournaments with n vertices (n odd). We conjecture that ν3(n) = (1 + o(1))n /9 and prove that n 11.43 (1− o(1)) ≤ ν3(n) ≤ n 9 (1 + o(1)) improving upon the best known upper bound of n −1 8 and lower bound of n 11.5 (1 − o(1)). The result is generalized to tournaments where the indegree and outdegree at each vertex may differ by at most βn.

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عنوان ژورنال:
  • Discrete Mathematics

دوره 338  شماره 

صفحات  -

تاریخ انتشار 2015