English

Empty Triangles in Generalized Twisted Drawings of $K_n$

Computational Geometry 2022-08-12 v1

Abstract

Simple drawings are drawings of graphs in the plane or on the sphere such that vertices are distinct points, edges are Jordan arcs connecting their endpoints, and edges intersect at most once (either in a proper crossing or in a shared endpoint). Simple drawings are generalized twisted if there is a point OO such that every ray emanating from OO crosses every edge of the drawing at most once and there is a ray emanating from OO which crosses every edge exactly once. We show that all generalized twisted drawings of KnK_n contain exactly 2n42n-4 empty triangles, by this making a substantial step towards proving the conjecture that this is the case for every simple drawing of KnK_n.

Keywords

Cite

@article{arxiv.2208.05819,
  title  = {Empty Triangles in Generalized Twisted Drawings of $K_n$},
  author = {Alfredo García and Javier Tejel and Birgit Vogtenhuber and Alexandra Weinberger},
  journal= {arXiv preprint arXiv:2208.05819},
  year   = {2022}
}

Comments

Appears in the Proceedings of the 30th International Symposium on Graph Drawing and Network Visualization (GD 2022)