The fractional chromatic number of Zykov products of graphs

نویسندگان

  • Pierre Charbit
  • Jean-Sébastien Sereni
چکیده

Zykov designed one of the oldest known family of triangle-free graphs with arbitrarily high chromatic number. We determine the fractional chromatic number of the Zykov product of a family of graphs. As a corollary, we deduce that the fractional chromatic numbers of the Zykov graphs satisfy the same recurrence relation as those of the Mycielski graphs, that is an+1 = an + 1 an . This solves a conjecture of Jacobs.

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عنوان ژورنال:
  • Appl. Math. Lett.

دوره 24  شماره 

صفحات  -

تاریخ انتشار 2011