1: 2 3 4 5
2: 1 5 6 7
3: 1 7 8 9
4: 1 9 10 11
5: 1 11 12 2
6: 2 12 13 7
7: 2 6 8 3
8: 3 7 13 14
9: 3 14 10 4
10: 4 9 15 16
11: 4 16 17 5
12: 5 17 18 6
13: 6 18 19 8
14: 8 19 15 9
15: 10 14 20 21
16: 10 21 22 11
17: 11 22 23 12
18: 12 23 24 13
19: 13 24 20 14
20: 15 19 25 21
21: 15 20 22 16
22: 16 21 25 17
23: 17 25 24 18
24: 18 23 25 19
25: 20 24 23 22