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