More on graphs with just three distinct eigenvalues
2017 ◽
Vol 11
(1)
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pp. 74-80
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Keyword(s):
Let G be a connected non-regular non-bipartite graph whose adjacency matrix has spectrum p,?(k),?(l), where k,l ? N and p > ? > ?. We show that if ? is non-main then ?(G) ? 1 + ? - ??, 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).
2013 ◽
Vol 5
(1)
◽
pp. 13
Keyword(s):
Keyword(s):
1977 ◽
Vol 29
(4)
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pp. 845-847
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Keyword(s):
2019 ◽
Vol 1334
◽
pp. 012020
2019 ◽
Vol 19
(3)
◽
pp. 673-680
2020 ◽
Vol 1564
◽
pp. 012032
Keyword(s):