# Lol or not Lol? Here is the log

Calculus Level 3

$\displaystyle \sum_{n = 1}^\infty \frac{1}{3^n n}$

The sum above can be written as $$S=\ln \left(\dfrac{a}{b}\right)$$, where $$a$$ and $$b$$ are coprime positive integers. Find $$a + b$$.

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