An improved bound for strongly regular graphs with smallest eigenvalue $-m$

Jack Koolen, Chenhui Lv, Greg Markowsky +1

In 1979, Neumaier gave a bound on $\hat{I}»$ in terms of $m$ and $\hat{I}¼$, where $-m$ is the smallest eigenvalue of a primitive strongly regular graph, unless the graph in question belongs t…