1, 1
1, 2
1, 3
1, 4
2, 1
2, 2
3, 1
3, 2
4, 1
4, 2
4, 3
5, 1
5, 2
5, 3
5, 4
5, 5
5, 6
5, 7
5, 8
5, 9
6, 1
6, 2
7, 1
7, 2
7, 3
7, 4
7, 5
7, 6
7, 7
7, 8
7, 9
8, 1
8, 2
9, 1
10, 1