Bicyclic graphs with exactly two main eigenvalues

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Unicyclic graphs with exactly two main eigenvalues

An eigenvalue of a graph G is called a main eigenvalue if it has an eigenvector the sum of whose entries is not equal to zero, and it is well known that a graph has exactly one main eigenvalue if and only if it is regular. In this work, all connected unicyclic graphs with exactly two main eigenvalues are determined. c © 2006 Elsevier Ltd. All rights reserved.

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ژورنال

عنوان ژورنال: Linear Algebra and its Applications

سال: 2009

ISSN: 0024-3795

DOI: 10.1016/j.laa.2009.06.022