Maxima: Differentiate sum at specific index-position

On 5/7/2013 8:28 AM, Robert Dodier wrote:
> On 2013-05-07, Stavros Macrakis <macrakis at alum.mit.edu> wrote:
>
>> Doing this really isn't that hard in principle, but as far as I know, no
>> one has actually done it.  See
>> http://www.math.utexas.edu/pipermail/maxima/2011/025302.html
>>
>> This seems to come up once a year or so... maybe we should do something
>> about it.
> Agreed ... it's one of those things that's on my perpetual to-do list.
> Of course if someone else will do it, that would be awesome.
>
> best
>
> Robert Dodier
>
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This kind of thing has been done repeatedly, some in Maxima./ Macsyma.
e.g.

CJ Smith, SIGSAM Bulletin 1984


  *Implementation of a package of tools for manipulation of sums*


or

M. Arcieri, A. Miloa, F. Pansiti

A Package of Tools for Manipulation of Sums and Series


and also in DE Knuth vol 2, I think, but not in programs there..
RJF