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arXiv · 0908.3545

Notes on large angle crossing graphs

Vida Dujmovic·Joachim Gudmundsson·Pat Morin·Thomas Wolle
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Abstract

A graph G is an a-angle crossing (aAC) graph if every pair of crossing edges in G intersect at an angle of at least a. The concept of right angle crossing (RAC) graphs (a=Pi/2) was recently introduced by Didimo et. al. It was shown that any RAC graph with n vertices has at most 4n-10 edges and that there are infinitely many values of n for which there exists a RAC graph with n vertices and 4n-10 edges. In this paper, we give upper and lower bounds for the number of edges in aAC graphs for all 0 < a < Pi/2.

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Vida Dujmovic, Joachim Gudmundsson, Pat Morin, Thomas Wolle. 2009-08-25. Notes on large angle crossing graphs. https://doi.org/10.4086/cjtcs.2011.004

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