Turán Graphs and the Number of Colorings

نویسنده

  • Serguei Norine
چکیده

We consider an old problem of Linial and Wilf to determine the structure of graphs which allow the maximum number of q-colorings among graphs with n vertices and m edges. We show that if r divides q then for all sufficiently large n the Turán graph Tr(n) has more q-colorings than any other graph with the same number of vertices and edges. This partially confirms a conjecture of Lazebnik. Our proof builds on methods of Loh, Pikhurko and Sudakov, which reduce the problem to a quadratic program.

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عنوان ژورنال:
  • SIAM J. Discrete Math.

دوره 25  شماره 

صفحات  -

تاریخ انتشار 2011