Perkel graph

Perkel graph
Perkel graphs with 19-fold symmetry
Vertices57
Edges171
Radius3
Diameter3
Girth5
Automorphisms3420
Chromatic number3
PropertiesRegular, distance-transitive
Table of graphs and parameters

In mathematics, the Perkel graph, named after Manley Perkel, is a 6-regular graph with 57 vertices and 171 edges. It is the unique distance-regular graph with intersection array (6, 5, 2; 1, 1, 3).[1] The Perkel graph is also distance-transitive.

It is also the skeleton of an abstract regular polytope, the 57-cell.

References

  1. ^ Coolsaet, K. and Degraer, J. "A Computer Assisted Proof of the Uniqueness of the Perkel Graph." Designs, Codes and Crypt. 34, 155–171, 2005.
  • Brouwer, A. E. Perkel Graph. [1].
  • Brouwer, A. E.; Cohen, A. M.; and Neumaier, A. The Perkel Graph for L(2,19). 13.3 in Distance Regular Graphs. New York: Springer-Verlag, pp. 401–403, 1989.
  • Perkel, M. Bounding the Valency of Polygonal Graphs with Odd Girth. Can. J. Math. 31, 1307-1321, 1979.
  • Perkel, M. Characterization of in Terms of Its Geometry.Geom. Dedicata 9, 291-298, 1980.
  • Weisstein, Eric W. "Perkel graph". MathWorld.