> -----Original Message-----
> From: maxima-bounces at math.utexas.edu
> [mailto:maxima-bounces at math.utexas.edu] On Behalf Of Edwin Woollett
> Sent: Sunday, February 24, 2008 3:24 PM
> To: maxima mailing list
> Subject: nusum
>
> Can someone explain how maxima uses the index limits for the
> function nusum.
It seems that maxima uses them better than you do.
> Is there a simple explanation for the ouputs:
> ----------------------------------------
> nusum( j, j, 0, 2 ); ----> 3
wouldn't this be 0+1+2?
> and
> nusum( j, j, 0, j ); ---> j*( j + 1 ) / 2
> -----------------------------------------------
It appears that nusum is not confused by your effort to confuse it, and
implicitly solves
the problems as though you have 2 j's.
nusum( f(j_the_index), j_the_index, 0, j_the_upper_limit)
where f(x):=x.
It then gives you the correct answer, in spite of yourself.
RJF