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arXiv · 2310.09058

A Note on Eigenvalues of Cayley Graphs

Arnbjörg Soffía Árnadóttir·Chris Godsil
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Abstract

A graph is called integral if all its eigenvalues are integers. A Cayley graph is called normal if its connection set is a union of conjugacy classes. We show that a non-empty integral normal Cayley graph for a group of odd order has an odd eigenvalue.

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Arnbjörg Soffía Árnadóttir, Chris Godsil. 2023-10-13. A Note on Eigenvalues of Cayley Graphs. https://doi.org/10.1016/j.laa.2023.12.002

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