Parity vertex colorings of binomial trees

نویسندگان

  • Petr Gregor
  • Riste Skrekovski
چکیده

We show for every k ≥ 1 that the binomial tree of order 3k has a vertex-coloring with 2k+1 colors such that every path contains some color odd number of times. This disproves a conjecture from [1] asserting that for every tree T the minimal number of colors in a such coloring of T is at least the vertex ranking number of T minus one.

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عنوان ژورنال:
  • Discussiones Mathematicae Graph Theory

دوره 32  شماره 

صفحات  -

تاریخ انتشار 2012