# Solving a weird series

Number Theory Level 5

$\sum_{n=1}^\infty \dfrac{d(n) }{n^2}$

Let $$d(n)$$ denote the number of positive divisors of integer $$n$$ inclusive of 1 and itself.

If the series above is equal to $$\dfrac {a \pi^b}c$$, where $$a,b,c$$ are positive integers with $$a,c$$ coprime, find the value of $$a+b+c$$.

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