, Volume 27, Issue 1, pp 63–68 | Cite as

On Order Types of Systems of Segments in the Plane



Let r(n) denote the largest integer such that every family \(\mathcal{C}\) of n pairwise disjoint segments in the plane in general position has r(n) members whose order type can be represented by points. Pach and Tóth gave a construction that shows r(n) < n log8/log9 (Pach and Tóth 2009). They also stated that one can apply the Erdős–Szekeres theorem for convex sets in Pach and Tóth (Discrete Comput Geom 19:437–445, 1998) to obtain r(n) > log16 n. In this note, we will show that r(n) > cn 1/4 for some absolute constant c.


Order types Convex sets Segments 


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© Springer Science+Business Media B.V. 2010

Authors and Affiliations

  1. 1.Courant InstituteNew YorkUSA

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