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تسجيل مستخدم جديدStrongly cospectral vertices in normal Cayley graphs
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Arnbj\\\"org Soff\\'ia \\'Arnad\\'ottir
تاريخ النشر
2021
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We prove an upper bound on the number of pairwise strongly cospectral vertices in a normal Cayley graph, in terms of the multiplicities of its eigenvalues. We use this to determine an explicit bound in Cayley graphs of $mathbb{Z}_2^d$ and $mathbb{Z}_4^d$. We also provide some infinite families of Cayley graphs of $mathbb{Z}_2^d$ with a set of four pairwise strongly cospectral vertices and show that such graphs exist in every dimension.
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