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Anton

We can just look at the top left corner of each square inside the n x n grid.

For the 1×1 square, there will be n x n of those. For the 2×2, we can see that the top left corner of the 2×2 square must be in a 4×4 square, so there are 16. As a result, the number of squares in nxn is:

n^2 + (n-1)^2 + (n-2)^2….(n-n)^2, which is just the sum of squares up to n. The formula for this is:

n(n+1)(2n+1)/6

Also, how do we use Latex again?