n | a(n) |
---|---|
0 | 1 |
1 | 1 |
2 | 2 |
3 | 12 |
4 | 90 |
5 | 546 |
6 | 6156 |
7 | 81432 |
8 | 942012 |
9 | 15114780 |
10 | 294765336 |
11 | 5069224656 |
12 | 108842183352 |
13 | 2770895886552 |
14 | 64609245619920 |
15 | 1742542175582496 |
16 | 55074355772360976 |
17 | 1626315165597840912 |
18 | 53331321825434963232 |
[1,1,2,12,90,546,6156,81432,942012,15114780, 294765336,5069224656,108842183352,2770895886552, 64609245619920,1742542175582496,55074355772360976, 1626315165597840912,53331321825434963232] |