n | a(n) |
---|---|
1 | 1 |
2 | 1 |
3 | 1 |
4 | 2 |
5 | 5 |
6 | 20 |
7 | 86 |
8 | 486 |
9 | 3495 |
10 | 31938 |
11 | 368832 |
12 | 5412981 |
13 | 100924470 |
14 | 2390092072 |
15 | 71686035608 |
16 | 2726514241955 |
17 | 131508854502755 |
18 | 8039052200861454 |
19 | 622678408143680652 |
[1,1,1,2,5,20,86,486,3495,31938,368832,5412981, 100924470,2390092072,71686035608,2726514241955, 131508854502755,8039052200861454, 622678408143680652] |