Suppose your career depends on solving sums like
or more intimidating ones as
and your magic tricks toolbox fail to handle it. What is the last resort?
I developed a Maxima package to either solve hypergeometric sums or prove they cannot be solved.
hipergeo is a hypergeometric package for the computer algebra system Maxima featuring:
- Sister Celine implementation;
- friendly link to Gosper implementation from `zeilberger' package;
- Builds full recurrence from Zeilberger's algorithm;
- Wilf-Zeilberger proof machinery along with WZ certificate implementation.
For Portuguese readers, you can refer to base text for usage, algorithms, theory, etc. Here you will have a pragmatic introduction to hypergeometric summation, 100% Maxima-oriented.
As for English readers, you can refer to the seminal A=B book by Petkovsek, Wilf and Zeilberger for more details on the algorithms and a deeper insight into the theory. (This book uses Maple and Mathematica computer algebra systems rather than open source Maxima.)
In Maxima, type
> load('hipergeo.mac');
in order to load the package and browse the examples in the same directory.
First example can merely be solved by first finding the anti-difference of the summand,
> summand(k) := k*k!;
> antidiff : gosper(summand, k);
k!
and, by applying the fundamental theorem of calculus, that sum becomes n! - 1.
Any help is appreciated, should you find any error please contact or send a pull request and I will be delighted to cite your amendment.