The Math Forum

Search All of the Math Forum:

Views expressed in these public forums are not endorsed by NCTM or The Math Forum.

Math Forum » Discussions » Inactive » comp.soft-sys.math.mathematica

Notice: We are no longer accepting new posts, but the forums will continue to be readable.

Topic: Finding a sum
Replies: 1   Last Post: Jul 20, 2012 11:44 PM

Advanced Search

Back to Topic List Back to Topic List Jump to Tree View Jump to Tree View   Messages: [ Previous | Next ]
Goyder Dr HGD

Posts: 59
Registered: 1/29/05
Finding a sum
Posted: Jul 20, 2012 3:57 AM
  Click to see the message monospaced in plain text Plain Text   Click to reply to this topic Reply

I feel the sum below should have a closed form. Am I wrong? A direct attack does not work. However, by experimenting I can sum a row but I can't sum all the rows. Any ideas? Thanks.

Sum[1/(x + I y - (n + I m)),
{n, -Infinity, Infinity}, {m, -Infinity,Infinity}]

Srow = 1/(x + I y) +
Sum[1/(x + I y - (n + I m)) + 1/(x + I y - (-n + I m)),
{n, 1 , Infinity}]

Sum[Srow + (Srow /. m -> -m), {m, 1, Infinity}]

Point your RSS reader here for a feed of the latest messages in this topic.

[Privacy Policy] [Terms of Use]

© The Math Forum at NCTM 1994-2018. All Rights Reserved.