Tournament pathwidth and topological containment

نویسندگان

  • Alexandra Ovetsky Fradkin
  • Paul D. Seymour
چکیده

We prove that for every set S of tournaments the following are equivalent: • there exists k such that every member of S has pathwidth at most k • there is a digraph H such that no subdivision of H is a subdigraph of any member of S • there exists k such that for each T ∈ S, there do not exist k vertices of T that are pairwise k-connected. As a consequence, we obtain a polynomial-time algorithm to test whether a tournament contains a subdivision of a fixed digraph H as a subdigraph.

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عنوان ژورنال:
  • J. Comb. Theory, Ser. B

دوره 103  شماره 

صفحات  -

تاریخ انتشار 2013