3. On the left half of the board, the number 21 is written, and on the right half, the number 8 is written. It is allowed to take an arbitrary number \(a\) from the left half of the board and an arbitrary number \(b\) from the right half of the board, compute the numbers \(ab\), \(a^3 + b^3\), and write \(ab\) on the left and \(a^3 + b^3\) on the right side of the board, respectively. Can the number 2013201420152016 be obtained on the board using such operations?