n | a(n) |
---|---|
1 | 0 |
2 | 1 |
3 | 2 |
4 | 3 |
5 | 6 |
6 | 15 |
7 | 36 |
8 | 114 |
9 | 396 |
10 | 1565 |
11 | 6756 |
12 | 31563 |
13 | 154370 |
14 | 785113 |
15 | 4099948 |
16 | 21870704 |
17 | 118624544 |
18 | 652485364 |
19 | 3631820462 |
20 | 20426666644 |
21 | 115949791342 |
22 | 663640383400 |
[0,1,2,3,6,15,36,114,396,1565,6756,31563,154370, 785113,4099948,21870704,118624544,652485364, 3631820462,20426666644,115949791342,663640383400] |