A note on order and eigenvalue multiplicity of strongly regular graphs. (English) Zbl 1329.05312
Colbourn, Charles J. (ed.), Algebraic design theory and Hadamard matrices. ADTHM, Lethbridge, Alberta, Canada, July 8–11, 2014. Selected papers based on the presentations at the workshop and at the workshop on algebraic design theory with Hadamard matrices: applications, current trends and future directions, Banff International Research Station, Alberta, Canada, July 11–13, 2014. Cham: Springer (ISBN 978-3-319-17728-1/hbk; 978-3-319-17729-8/ebook). Springer Proceedings in Mathematics & Statistics 133, 209-212 (2015).
Summary: In this note, we consider a well-known upper bound for the order of a strongly regular graph in terms of the multiplicity of a non-principal eigenvalue of its adjacency matrix.
For the entire collection see [Zbl 1329.05003].
For the entire collection see [Zbl 1329.05003].
MSC:
| 05E30 | Association schemes, strongly regular graphs |
| 05C50 | Graphs and linear algebra (matrices, eigenvalues, etc.) |
References:
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