n | a(n) |
---|---|
1 | 1 |
2 | 1 |
3 | 1 |
4 | 3 |
5 | 7 |
6 | 20 |
7 | 131 |
8 | 815 |
9 | 5142 |
10 | 36800 |
11 | 272093 |
12 | 2077909 |
13 | 16176607 |
14 | 127997683 |
15 | 1025727646 |
16 | 8310377815 |
17 | 68217725764 |
18 | 560527576100 |
19 | 4556993996246 |
[1,1,1,3,7,20,131,815,5142,36800,272093,2077909, 16176607,127997683,1025727646,8310377815, 68217725764,560527576100,4556993996246] |