# Inspired by Mr. $$\pi$$ (The force awakens)

Algebra Level 5

Let $$a_1, a_2, \ldots , a_n$$ be the roots of the polynomial $$\displaystyle \sum_{k=1}^n kx^k = 0$$. If $$\displaystyle \sum_{k=1}^n \dfrac1{(1-a_k)^2} = -13$$, find $$n$$.

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