English

Existence results for pentagonal geometries

Combinatorics 2020-07-22 v1 Discrete Mathematics

Abstract

New results on pentagonal geometries PENT(k,r) with block sizes k = 3 or k = 4 are given. In particular we completely determine the existence spectra for PENT(3,r) systems with the maximum number of opposite line pairs as well as those without any opposite line pairs. A wide-ranging result about PENT(3,r) with any number of opposite line pairs is proved. We also determine the existence spectrum of PENT(4,r) systems with eleven possible exceptions.

Keywords

Cite

@article{arxiv.2007.10810,
  title  = {Existence results for pentagonal geometries},
  author = {Anthony D. Forbes and Terry S. Griggs and Klara Stokes},
  journal= {arXiv preprint arXiv:2007.10810},
  year   = {2020}
}
R2 v1 2026-06-23T17:16:52.509Z