English

On Distance-Regular Graphs with Smallest Eigenvalue at Least $-m$

Combinatorics 2009-08-17 v1 Spectral Theory

Abstract

A non-complete geometric distance-regular graph is the point graph of a partial geometry in which the set of lines is a set of Delsarte cliques. In this paper, we prove that for fixed integer m2m\geq 2, there are only finitely many non-geometric distance-regular graphs with smallest eigenvalue at least m-m, diameter at least three and intersection number c22c_2 \geq 2.

Keywords

Cite

@article{arxiv.0908.2017,
  title  = {On Distance-Regular Graphs with Smallest Eigenvalue at Least $-m$},
  author = {J. H. Koolen and S. Bang},
  journal= {arXiv preprint arXiv:0908.2017},
  year   = {2009}
}
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