These are implementations of the algorithms in the book "A=B", as well as
(maybe) some generalizations and other sage tools for experimental mathematics.  

The algorithms in question are for evaluating hypergeometric sums in closed form.

The book is available online here:

http://www.math.upenn.edu/~wilf/AeqB.html

The goal, currently, is just to get the algorithms working, not to get the most
efficient possible implementation.