k=0 n=50 for i in [1..n]: k=k+i^2 print '1^2 + 2^2 + ... +', n^2, '=', k
f=x^2 n=50 print '1^2 + 2^2 + ... +', n^2, '=', sum(f,x,1,n)
n*(n+1)*(2*n+1)/6