On Sep 17, 3:17 pm, sps <[email protected]> wrote:
> Can you explicitly write the results?

This might help you:


(%i2) display2d:false;

(%o2) false
(%i3) load(simplify_sum);

(%o3) "/Users/.../sage-4.4.4/local/share/maxima/5.20.1/share/contrib/
solve_rec/simplify_sum.mac"
(%i4) simplify_sum(sum(((2*%i)^n/(n^3+1)*(1/4)^n),n,0,inf))
;

(%o4) %f[4,3]([1,1,-(sqrt(3)*%i+1)/2,(sqrt(3)*%i-1)/2],
              [2,-(sqrt(3)*%i-1)/2,(sqrt(3)*%i+1)/2],%i/2)

So this is the hypergeometric function F_{4,3} (where usually the 4 is
on the left and  the three on the right) evaluated at the values 1, 1,
and so one, where %i is just one of the square roots of negative one.
You'll note that there are two sets of things to evaluate it at, plus
the third (i/2).  These are not necessarily easy to compute.

See http://mathworld.wolfram.com/GeneralizedHypergeometricFunction.html,
for instance.  I don't know that I can make this any easier to
compute, though!  But unfortunately I cannot make the hypergeometric
functions easy (though they are very useful).

I'm not quite sure if this is the answer you are looking for or not,
so let us know.

- kcrisman

-- 
To post to this group, send email to [email protected]
To unsubscribe from this group, send email to 
[email protected]
For more options, visit this group at 
http://groups.google.com/group/sage-support
URL: http://www.sagemath.org

Reply via email to