Counting K4-subdivisions

نویسندگان

  • Tillmann Miltzow
  • Jens M. Schmidt
  • Mingji Xia
چکیده

A fundamental theorem in graph theory states that any 3-connected graph contains a subdivision of K4. As a generalization, we ask for the minimum number of K4-subdivisions that are contained in every 3connected graph on n vertices. We prove that there are Ω(n) such K4subdivisions and show that the order of this bound is tight for infinitely many graphs. We further prove that the computational complexity of the problem of counting the exact number of K4-subdivisions is #P -hard.

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عنوان ژورنال:
  • Discrete Mathematics

دوره 338  شماره 

صفحات  -

تاریخ انتشار 2015