In the 3 × 3 square on the left, the numbers from 1 to 9 have been filled so that the sum in each row / column / diagonal adds up to 15. If the same exercise is to be carried out for the 4 × 4 square, using the numbers from 1 to 16, what will be the sum of the numbers in each row / column / diagonal? [Figure: see page 3 of source PDF]