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   <dc:title>On k-gons and k-holes in point sets</dc:title>
   <dc:creator>Aichholzer, Oswin</dc:creator>
   <dc:creator>Fabila Monroy, Ruy</dc:creator>
   <dc:creator>Gonzalez Aguilar, Hernan</dc:creator>
   <dc:creator>Hackl, Thomas</dc:creator>
   <dc:creator>Heredia, Marco A.</dc:creator>
   <dc:creator>Huemer, Clemens</dc:creator>
   <dc:creator>Urrutia Galicia, Jorge</dc:creator>
   <dc:creator>Valtr, Pavel</dc:creator>
   <dc:creator>Vogtenhuber, Birgit</dc:creator>
   <dc:subject>Àrees temàtiques de la UPC::Matemàtiques i estadística</dc:subject>
   <dc:subject>Graph theory</dc:subject>
   <dc:subject>Erdos-Szekeres type problems</dc:subject>
   <dc:subject>k-Gons</dc:subject>
   <dc:subject>k-Holes</dc:subject>
   <dc:subject>Empty k-gons</dc:subject>
   <dc:subject>empty convex polygons</dc:subject>
   <dc:subject>lower bounds</dc:subject>
   <dc:subject>number</dc:subject>
   <dc:subject>Grafs, Teoria de</dc:subject>
   <dcterms:abstract>We consider a variation of the classical Erdos-Szekeres problems on the existence and number of convex k-gons and k-holes (empty k-gons) in a set of n points in the plane. Allowing the k-gons to be non-convex, we show bounds and structural results on maximizing and minimizing their numbers. Most noteworthy, for any k and sufficiently large n, we give a quadratic lower bound for the number of k-holes, and show that this number is maximized by sets in convex position. (C) 2014 Elsevier B.V. All rights reserved.</dcterms:abstract>
   <dcterms:abstract>Postprint (author's final draft)</dcterms:abstract>
   <dcterms:issued>2015-08-01</dcterms:issued>
   <dc:type>Article</dc:type>
   <dc:rights>http://creativecommons.org/licenses/by-nc-nd/3.0/es/</dc:rights>
   <dc:rights>Open Access</dc:rights>
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