problem with Sum
- To: mathgroup at smc.vnet.net
- Subject: [mg100631] problem with Sum
- From: olfa <olfa.mraihi at yahoo.fr>
- Date: Wed, 10 Jun 2009 05:31:11 -0400 (EDT)
Hi mathematica community,
I have this input: Sum[a[k], {k, 1, j}] - Sum[a[k], {k, 1, i+j-n}]
How it is possible to let mathematica gives as output:
Sum[a[k], {k, i+j-n+1, j}] if i+j-n<j
and Sum[a[k], {k, j+1, i+j-n}] if i+j-n>j
thank you very much.