Bimonster

The wreathed product of the Monster Group by . The bimonster is a quotient of the Coxeter Group with the following Coxeter-Dynkin Diagram.

$\begin{figure}\begin{center}\BoxedEPSF{BimonsterGraph.epsf scaled 500}\end{center}\end{figure}$

This had been conjectured by Conway, but was proven around 1990 by Ivanov and Norton. If the parameters in Coxeter's Notation $[3^{p,q,r}]$ are written side by side, the bimonster can be denoted by the Beast Number 666.