English

Plane point sets with many squares or isosceles right triangles

Combinatorics 2021-12-24 v1 Metric Geometry

Abstract

How many squares are spanned by nn points in the plane? Here we study the corresponding maximum possible number S(n)S_{\square}(n) of squares and determine the exact values for all n17n\le 17. For 18n10018\le n\le 100 we give lower bounds for S(n)S_{\square}(n). Besides that a few preliminary structural results are obtained. For the related problem of the maximum possible number of isosceles right triangles we determine the exact values for n14n\le 14 and give lower bounds for 15n5015\le n\le 50.

Keywords

Cite

@article{arxiv.2112.12716,
  title  = {Plane point sets with many squares or isosceles right triangles},
  author = {Sascha Kurz},
  journal= {arXiv preprint arXiv:2112.12716},
  year   = {2021}
}

Comments

31 pages, 9 tables, 10 figures

R2 v1 2026-06-24T08:30:03.213Z