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

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Goyder Dr HGD

Posts: 59
Registered: 1/29/05
Finding a sum
Posted: Jul 20, 2012 3:57 AM
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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}]




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