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arXiv · 1612.00589

Graphs with two main and two plain eigenvalues

Sakander Hayat·Muhammad Javaid·Jack H. Koolen
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Abstract

In this paper, we introduce the concepts of the plain eigenvalue, the main-plain index and the refined spectrum of graphs. We focus on the graphs with two main and two plain eigenvalues and give some characterizations of them.

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Sakander Hayat, Muhammad Javaid, Jack H. Koolen. 2016-12-02. Graphs with two main and two plain eigenvalues. https://arxiv.org/abs/1612.00589

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