[seqfan] Re: Generally known (to those who know of such things)

[N. J. A. Sloane]

> It isn't at all obvious to me why this should be called a "class 
number"; what are the classes being numbered?

Class numbers are part of classical num ber theory.  Don't
go to the web, go to the library and look at any book
on number theory.  E.g. Borevich and Sharevich, "Number Theory",
or Edwards, "Fermat's Last Theorem", to pick two at random!

 Best regards
 			 Neil