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a bit mathematics will do the trick to:

sum of 1 + 2 + .. + n = n(n+1)/2

sum of 1^2 + 2^2 + 3^2 + ... n^2 = n(n+1)(2n+1)/6

sqrt(2119) = 46

so the answer is: 2118*2119/2 + 46*47*93/6