Packing six T-joins in plane graphs

نویسندگان

  • Zdenek Dvorak
  • Ken-ichi Kawarabayashi
  • Daniel Král
چکیده

Let G be a plane graph and T an even subset of its vertices. It has been conjectured that if all T -cuts of G have the same parity and the size of every T -cut is at least k, then G contains k edge-disjoint T -joins. The case k = 3 is equivalent to the Four Color Theorem, and the cases k = 4, which was conjectured by Seymour, and k = 5 were proved by Guenin. We settle the next open case k = 6.

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

دوره 116  شماره 

صفحات  -

تاریخ انتشار 2016