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arXiv · 2511.14496

An integral family of quasi-strongly regular Cayley graphs

Sauvik Poddar·Sucharita Biswas·Angsuman Das
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Abstract

Quasi-strongly regular graphs form a significant generalization of strongly regular graphs. We study the eigenvalues of a family of such graphs, $Γ_H(G)$, constructed from a finite group $G$ and a subgroup $H$. Our main results include a sufficient condition for $Γ_H(G)$ to be integral and an explicit computation of its entire spectrum when $H$ is normal, revealing that the spectrum in this case depends only on $|G|$ and the index $[G:H]$.

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Sauvik Poddar, Sucharita Biswas, Angsuman Das. 2025-11-18. An integral family of quasi-strongly regular Cayley graphs. https://arxiv.org/abs/2511.14496

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