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arXiv · 2611.07407

The Higman-Sims graph and a geometric construction of the Steiner system $S(3,6,22)$

Mahdi Ebrahimi
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Abstract

The Higman-Sims graph is the unique strongly regular graph with parameters $(100,22,0,6)$. In this paper, we show that the only distance-regular antipodal double cover of the Higman-Sims graph is its bipartite double cover. Our main tool is a geometric construction of the Steiner system $S(3,6,22)$.

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Mahdi Ebrahimi. 2026-11-05. The Higman-Sims graph and a geometric construction of the Steiner system $S(3,6,22)$. https://arxiv.org/abs/2611.07407

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