We investigate strongly regular graphs for which Hoffman's ratio bound and Cvetcović's inertia bound are equal. This means that ve−=m−(e−−k), where v is the number of vertices, k is the regularity, e− is the smallest eigenvalue, and m− is the multiplicity of e−. We show that Delsarte cocliques do not exist for all Taylor's 2‐graphs and for point graphs of generalized quadrangles of order (q,q2−q) for infinitely many q. For cases where equality may hold, we show that for nearly all parameter sets, there are at most two Delsarte cocliques.
Journal of Combinatorial Designs – Wiley
Published: Jan 1, 2018
Keywords: ; ; ; ; ; ; ; ;
It’s your single place to instantly
discover and read the research
that matters to you.
Enjoy affordable access to
over 12 million articles from more than
10,000 peer-reviewed journals.
All for just $49/month
It’s easy to organize your research with our built-in tools.
All the latest content is available, no embargo periods.
“Whoa! It’s like Spotify but for academic articles.”@Phil_Robichaud