Rooted grid minors

نویسندگان

  • Dániel Marx
  • Paul D. Seymour
  • Paul Wollan
چکیده

Intuitively, a tangle of large order in a graph is a highly-connected part of the graph, and it is known that if a graph has a tangle of large order then it has a large grid minor. Here we show that for any k, if G has a tangle of large order and Z is a set of vertices of cardinality k that cannot be separated from the tangle by any separation of order less than k, then G has a large grid minor containing Z, in which the members of Z all belong to the outside of the grid. This is a lemma for use in a later paper.

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

دوره 122  شماره 

صفحات  -

تاریخ انتشار 2017