Quadratic Embedding Constants of Strongly Regular Graphs

Nobuaki Obata

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arXiv · 2501.01020

Quadratic Embedding Constants of Strongly Regular Graphs

Nobuaki Obata

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Abstract

We obtain an explicit formula for the quadratic embedding constant (QEC) of a strongly regular graph $\mathrm{srg}(n,k,λ,μ)$ with $μ\ge1$. By using QEC we give a necessary and sufficient condition for a strongly regular graph to admit a quadratic embeddingin a Euclidean space.

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BibTeX RIS

Nobuaki Obata. 2025-01-02. Quadratic Embedding Constants of Strongly Regular Graphs. https://arxiv.org/abs/2501.01020

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