Strongly regular graphs with parameters (85,14,3,2) do not exist
Combinatorics
2025-04-04 v1
Abstract
We investigate the second smallest unresolved feasible set of parameters of strongly regular graphs, . Using the classification of cubic graphs of small degree, we restrict possible local structure of such a graph . After that, we exhaustively enumerate possible neighbourhoods of a maximal -clique of and check them against a variety of conditions, including the combinatorial ones, coming from and , as well as the linear algebra ones, utilising the Euclidean representation of . These conditions yield contradiction in all cases, and hence, no exists.
Keywords
Cite
@article{arxiv.2504.02449,
title = {Strongly regular graphs with parameters (85,14,3,2) do not exist},
author = {Sergey Shpectorov and Tianxiao Zhao},
journal= {arXiv preprint arXiv:2504.02449},
year = {2025}
}