English

Cospectral mates for generalized Johnson and Grassmann graphs

Combinatorics 2023-05-29 v1

Abstract

We provide three infinite families of graphs in the Johnson and Grassmann schemes that are not uniquely determined by their spectrum. We do so by constructing graphs that are cospectral but non-isomorphic to these graphs.

Keywords

Cite

@article{arxiv.2305.16858,
  title  = {Cospectral mates for generalized Johnson and Grassmann graphs},
  author = {Aida Abiad and Jozefien D'haeseleer and Willem H. Haemers and Robin Simoens},
  journal= {arXiv preprint arXiv:2305.16858},
  year   = {2023}
}
R2 v1 2026-06-28T10:47:27.289Z