## How to prove the identity $\sum_{n=1}^{\infty} \dfrac{{H_{n}}^2}{n^2} = \dfrac{17}{360} {\pi}^4$ February 14

Prove That $$\sum_{n=1}^{\infty} \dfrac{{H_{n}}^2}{n^2} = \dfrac{17}{360} {\pi}^4$$ I encountered this identity while reading the article about Harmonic Number on Wikipedia. I thought of using the integral representation of Harmonic Number, but the s