missing simpsum identity?



>>>>> "Mike" == Mike Valenzuela <mickle.mouse at gmail.com> writes:

    Mike> So one can arrive at the following in one of two ways:

    Mike> alt1: sum( (k+1-i)*b^(i), i, 1, k), simpsum;

    Mike> alt2: radcan( sum(sum(b^k,k,1,i),i,1,k) ),simpsum;



[snip]

    Mike> Logically, these two seem the same to me. Numerically these
    Mike> two appear the same over what I've tested. However, I cannot
    Mike> find a way to make Maxima simplify alt1 into the closed form
    Mike> expression generated by alt2.

    Mike> Thus, I am asking something along the lines of "How do I
    Mike> make Maxima simplify alt1 into alt2's non-summation form?"

I find that simpsum is not very powerful.  If you load("simplify_sum")
and do simplify_sum(alt1) and simplify_sum(<sum in alt2>), you can see
that they are the equivalent.

Ray