# 400 Followers Problem

Algebra Level 4

$\large \displaystyle \sum^{10}_{n=1}\dfrac{2^{n-1}}{1+2^n+2^{n+1}+2^{2n+1}}$ If the summation above is equal to $$\dfrac AB$$, where $$A$$ and $$B$$ are coprime positive integers, find the value of $$A+B$$.

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