1 2-3 4-5 6-7 8-9 10-11 12-13 14-15 16-17 18-19 20
1 2-3 4-5 6-7 8-9 10-11 12-13 14-15 16-17 18-19 20-21 22-23 24-25 26-27 28-29 30-31 32
