2 2 2 3 5 6 2 5 2 2 = 2 + + 3 + + 5 + + 2 + 5 + 6 2 = (2 + 1) + (3 + 1) + (5 + 1) + 2 + 11 2 = 3 + 4 + 6 + 2 + 11 − = − = − ( )