A
factorial function built from a
factorial hyper4 to itself.
It follows this form:
n$ = n!
(4)n! = n!
n!n!...n!
Note: the '$' is a
factorial sign with an S written over it.
More info: http://home.earthlink.net/~mrob/pub/math/largenum-2.html
This writeup is under the GNU Free Documentation License