English

The maximum number of intersections of two polygons

Combinatorics 2015-02-11 v2 Discrete Mathematics

Abstract

We investigate the maximum number of intersections between two polygons with p and q vertices, respectively, in the plane. The cases where p or q is even or the polygons do not have to be simple are quite easy and already known, but when p and q are both odd and both polygons are simple, the problem is more difficult. The conjectured maximum is (p-1)(q-1)+2 for all odd p and q.

Keywords

Cite

@article{arxiv.1207.0996,
  title  = {The maximum number of intersections of two polygons},
  author = {Felix Günther},
  journal= {arXiv preprint arXiv:1207.0996},
  year   = {2015}
}

Comments

This paper has been withdrawn by the author due to an unrecoverable error in the proof of Lemma 2. In fact, a counterexample to an even weaker version of Lemma 2 has been found by the author