1, 2, 3a

a 4, 5

a 6, 7, 8

a 9, 10

a 11, 12, 13

a 14, 15

a 16, 17,18

a 19, 20

a 21, 22, 23

a 24, 25

a 26, 27

a 28, 29,x

b 1, 2, 3

b 4, 5

b 6, 7, 8

b 9, 10

b 11, 12,x

b 13, 14

b 15, 16,x

b 17, 18

b 19, 20, 21

b 22, 23

b 24, 25,26

b 27, 28