TITLE: An Identity Concerning the Riemann Zeta Function
QUESTION [5 upvotes]: Let $\zeta$ be the Riemann- Zeta function. For any integer, $n \geq 2$, how to prove $$\zeta(2) \zeta(2n-2) + \zeta(4)\zeta(2n-4) + \cdots + \zeta(2n-2)\zeta(2) = \Bigl(n + \frac{1}{2}\Bigr)\zeta(2n)$$

REPLY [14 votes]: This is too nice an exercise to give away. Your starting point should be:
$$\frac{t}{e^t-1} = 1 - t/2 + \frac{2 \zeta(2)}{(2 \pi)^2} t^2 - \frac{2 \zeta(4)}{(2 \pi)^4} t^4 + \frac{2 \zeta(6)}{(2 \pi)^6} t^6 - \cdots.$$