Thread: sum of squares

For an equation such as below:

(n1)^2 + (n2)^2 + (n3)^2 = 7^2 = 49

How would you figure out how many combinations of differents n's there are to satisfy the above equation? Or in general,

(n1)^2 + (n2)^2 + (n3)^2 = N^2

Thanks

See here.