Question 87
Andriy has counted the sum of the squares of positive integers from $1$ to $2016$, Vitaliy has counted the sum of the natural numbers from $1$ to $2016$. Yuriy has added Andriy's and Vitaliy's numbers, multiplied by $3$ and added $2016$. What number has Yuriy got?
(Andriy Anikushin)
(Andriy Anikushin)