Triangle-Free Geometric Intersection Graphs with No Large Independent Sets
نویسنده
چکیده
It is proved that there are triangle-free intersection graphs of line segments in the plane with arbitrarily small ratio between the maximum size of an independent set and the total number of vertices.
منابع مشابه
Triangle-free geometric intersection graphs with large chromatic number
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For a graph G and an integer k ≥ 2, let χk(G) denote the minimum number of colors in a coloring of the vertices of G such that no k-clique of G is monochromatic. In particular, χ2(G) is the ordinary chromatic number of G. It is known that triangle-free segment intersection graphs can have arbitrarily large chromatic number. It is also known that Kk-free string graphs can have arbitrarily large ...
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ورودعنوان ژورنال:
- Discrete & Computational Geometry
دوره 53 شماره
صفحات -
تاریخ انتشار 2015