Respuesta :

You need to know the following:

sigma(i) = 1/2 * i * (i+1)

sigma(i^2) = 1/6 * i * (i+1) * (2i+1)

Therefore, the answer should be 14( i(i+1) + i * (i+1) * (2i+1)) = 14i(i+1)(2i+2) = 28i(i+1)^2