Summation giving incorrect value (I think) in Mathematica

Question

I have the problem $\displaystyle\sum\limits_{x=2}^4 \dfrac{1}{x^2}$. I know the answer to this problem should be $\dfrac{61}{144}$. When I type the problem into Wolfram Mathematica, I get the answer $\dfrac{205}{144}$.

Is there something wrong with my syntax? I'm new to Mathematica:

x = 2
Sum[(1/x^2), {x, 4}]

Answer 1

In Mathematica, the bound variable in Sum starts at 1 when the second argument is in the form {x,n}. It is also defined locally, so setting its value outside changes nothing. To make it start from 2, use {x,2,4} as the second argument. But this is really a question for Mathematica Stack Exchange.