Abstract
Let P be a set of n points in general and convex position in the plane. Let D n be the graph whose vertex set is the set of all line segments with endpoints in P, where disjoint segments are adjacent. The chromatic number of this graph was first studied by Araujo et al. [CGTA, 2005]. The previous best bounds are \(\frac{3n}{4}\leq \chi(D_n) <n-\sqrt{\frac{n}{2}}\) (ignoring lower order terms). In this paper we improve the lower bound to \(\chi(D_n)\geq n-\sqrt{2n}\), achieving near-tight bounds on χ(D n ).
Dedicat al nostre amic i mestre Ferran Hurtado.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Preview
Unable to display preview. Download preview PDF.
Similar content being viewed by others
References
Araujo, G., Dumitrescu, A., Hurtado, F., Noy, M., Urrutia, J.: On the chromatic number of some geometric type Kneser graphs. Comput. Geom. Theory Appl. 32(1), 59–69 (2005)
Cairns, G., Nikolayevsky, Y.: Bounds for generalized thrackles. Discrete Comput. Geom. 23(2), 191–206 (2000)
Cairns, G., Nikolayevsky, Y.: Generalized thrackle drawings of non-bipartite graphs. Discrete Comput. Geom. 41(1), 119–134 (2009)
Cairns, G., Nikolayevsky, Y.: Outerplanar thrackles. Graphs and Combinatorics 28(1), 85–96 (2012)
Dujmović, V., Wood, D.R.: Thickness and antithickness (2010) (in preparation)
Fenchel, W., Sutherland, J.: Lösung der aufgabe 167. Jahresbericht der Deutschen Mathematiker-Vereinigung 45, 33–35 (1935)
Hopf, H., Pammwitz, E.: Aufgabe no. 167. Jahresbericht der Deutschen Mathematiker-Vereinigung 43 (1934)
Lovász, L., Pach, J., Szegedy, M.: On Conway’s thrackle conjecture. Discrete Comput. Geom. 18(4), 369–376 (1997)
Woodall, D.R.: Thrackles and deadlock. In: Combinatorial Mathematics and its Applications (Proc. Conf., Oxford, 1969), pp. 335–347. Academic Press, London (1971)
Author information
Authors and Affiliations
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2012 Springer-Verlag Berlin Heidelberg
About this chapter
Cite this chapter
Fabila-Monroy, R., Wood, D.R. (2012). The Chromatic Number of the Convex Segment Disjointness Graph. In: Márquez, A., Ramos, P., Urrutia, J. (eds) Computational Geometry. EGC 2011. Lecture Notes in Computer Science, vol 7579. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-642-34191-5_7
Download citation
DOI: https://doi.org/10.1007/978-3-642-34191-5_7
Publisher Name: Springer, Berlin, Heidelberg
Print ISBN: 978-3-642-34190-8
Online ISBN: 978-3-642-34191-5
eBook Packages: Computer ScienceComputer Science (R0)