[Maxima] I cannot load zeilberger package |||| nusum & Zeilberger

[Michel Van den Bergh]

>
> Zeilberger has its own implementation of Gosper algorithm. You can use
> it directly with GosperSum. Zeilberger will use the Gosper algorithm
> if gosper_in_zeilberger is set to true (which is the default).
>   

Don't forget that GosperSum included with Zeilberger has some bad bugs. Try

 GosperSum(-1/(n*(n+1)),n,1,k);

and

 GosperSum(1/(n*(n+1)),n,1,k);

Michel