Note on the number of edges in families with linear union-complexity
نویسندگان
چکیده
We give a simple argument showing that the number of edges in the intersection graph G of a family of n sets in the plane with a linear unioncomplexity is O(ω(G)n). In particular, we prove χ(G) 6 col(G) < 19ω(G) for intersection graph G of a family of pseudo-discs, which improves a previous
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