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The Hoffman-Singleton graph and its automorphisms. (English) Zbl 1021.05046
Summary: We describe the Hoffman-Singleton graph geometrically, showing that it is closely related to the incidence graph of the affine plane over $$\mathbb{Z}_5$$. This allows us to construct all automorphisms of the graph.

##### MSC:
 05C25 Graphs and abstract algebra (groups, rings, fields, etc.)
##### Keywords:
Hoffman-Singleton graph; automorphisms; biaffine plane
Full Text:
##### References:
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