A new entry for an updated Encyclopedia of Sociometrics. In reviewing such a work, there is no point in carping about what is missing or about the total inadequacy of such and such an entry. I'd rather enjoy what's there. And in the CEM there is much to enjoy. There is a significant non-overlap between any two of them.
Special functions are all over the place.
A sufficiency of recreational material of the Martin Gardner variety is incorporated into the text to amuse the casual reader or stimulate math buffs into buffistic creativity. There are more than 2000. Some entries are given long treatments. As balance, or as a show of indifference, many entries get short shrift with a rapidly sung nunc dimittis. The pages teem with references.