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On graphs with multiple eigenvalues

โœ Scribed by Peter Rowlinson

Book ID
104156430
Publisher
Elsevier Science
Year
1998
Tongue
English
Weight
811 KB
Volume
283
Category
Article
ISSN
0024-3795

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โœฆ Synopsis

Let ,~(ll) be an eigenspace of a finite graph G, with dimension m and codimension t > I. It is shown that if It ~ {-1,0} then m ~< ~ (t -l)(t + 4). A necessary and sufficient condition for It to be a multiple eigenvalue of G is established, and used to construct

examples from iratersecting families of sets.

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