Article
Details
Citation
Rowlinson P (2017) More on graphs with just three distinct eigenvalues. Applicable Analysis and Discrete Mathematics, 11, pp. 74-80. https://doi.org/10.2298/AADM161111033R
Abstract
Let G be a connected non-regular non-bipartite graph whose adjacency matrix has spectrum ρ, µ(k) , λ(l) , where k, l ∈ IN and ρ > µ > λ. We show that if µ is non-main then δ(G) ≥ 1 + µ − λµ, with equality if and only if G is of one of three types, derived from a strongly regular graph, a symmetric design or a quasi-symmetric design (with appropriate parameters in each case).
Journal
Applicable Analysis and Discrete Mathematics: Volume 11
Status | Published |
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Publication date | 31/12/2017 |
Date accepted by journal | 11/11/2016 |
URL | http://hdl.handle.net/1893/25320 |
Publisher | University of Belgrade |
ISSN | 1452-8630 |
People (1)
Emeritus Professor, Mathematics