1,1,
2,2,
3,3, 4, 5, 6,
4,7,
5,8,
6,9,
7,7, 10,
8,11,
9,11,
10,11,
11,12,
12,13,
13,13,
14,14,
15,14,
16,14,
17,15,
18,15,
19,16,
20,17,
21,18,
22,19, 20,
23,—,
24,33,
25,21,
26,34,
27,32,
28,9, 15, 16, 22,
29,23,
30,25, 27, 28,
31,28, 29, 32,
32,30,
33,31,
34,35,
35,37,
36,38,
37,39,
,,