# Complex analysis applications-II

Calculus Level 5

$\large \sum_{n = -\infty}^\infty \frac{1}{(1 + i + n)^2}$

Evaluate to 6 decimal places. Note that the summation is indexed by $$n$$, and that $$i$$ denotes the imaginary unit.

Bonus: Find a beautiful closed form for the sum.

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