## How would one do the following

How would one do the following sum?

$$\sum\limits_{n=1}^\infty n e^{- \epsilon~n^2}$$
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 Recognitions: Homework Help First of all, find out what epsilon is.

Recognitions:
Homework Help
 How would one do the following sum?
...carefully. What have you tried?

note $$\frac{d}{dn}e^{-\epsilon n^2}=-2\epsilon ne^{-\epsilon n^2}$$ ... may or may not be helpful.