engleski

On the 486-vertex distance-regular graphs of Koolen-Riebeek and Soicher

This paper considers three imprimitive distance-regular graphs with 486 vertices and diameter 4: the Koolen–Riebeek graph (which is bipartite), the Soicher graph (which is antipodal), and the incidence graph of a symmetric transversal design obtained from the affine geometry AG(5, 3) (which is both). It is shown that each of these is preserved by the same rank-9 action of the group 3^5:(2×M10), and the connection is explained using the ternary Golay code.

graph ; coset graph ; distance-regular graph

nije evidentirano