Coloring intersection graphs of x-monotone curves in the plane

نویسنده

  • Andrew Suk
چکیده

A class of graphs G is χ-bounded if the chromatic number of the graphs in G is bounded by some function of their clique number. We show that the class of intersection graphs of simple families of x-monotone curves in the plane intersecting a vertical line is χ-bounded. As a corollary, we show that the class of intersection graphs of rays in the plane is χ-bounded, and the class of intersection graphs of unit segments in the plane is χ-bounded.

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عنوان ژورنال:
  • Combinatorica

دوره 34  شماره 

صفحات  -

تاریخ انتشار 2014