Decomposing the Higman-Sims graph into double Petersen graphs

نویسندگان

  • Ivana Ilić
  • Spyros S. Magliveras
چکیده

It has been known for some time that the Higman-Sims graph can be decomposed into the disjoint union of two Hoffman-Singleton graphs. In this paper we establish that the Higman-Sims graph can be edge decomposed into the disjoint union of 5 double-Petersen graphs, each on 20 vertices. It is shown that in fact this can be achieved in 36960 distinct ways. It is also shown that these different ways fall into a single orbit under the automorphism group HS of the graph. 2000 Mathematics Subject Classification: 68P25, 94A60.

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تاریخ انتشار 2011