What is the following sum?

\[\sum (1+\frac{1}{2^2} + \frac{1}{3^2} + \dots + \frac{1}{100^2})\]

You can calculate the vector sum using the sum() function. Store your solution in the sum variable.

Hint: thanks to Euler, we know it should be close to \(\frac{\pi^2}{6}\).