Before 1
Number before 4
3
Number after 4
5
Number Before 5
4
Number after 17
18
Number before 18
17
Number before 7
6
Number after 6
7
Number before 9
8
Number after 2
3
Number before 2
1
Number before 12
11
Number after 9
10
Number before 14
13
Number after 14
15
Number before 6
5
Number before 15
14
Number after 11
12
Number before 17
16
Number after 8
9
Number before 16
15
Number before 20
19
Number after 19
20
Number before 19
18
Number after 16
17
Number before 8
7