n | a(n) |
---|---|
1 | 1 |
2 | 2 |
3 | 9 |
4 | 72 |
5 | 840 |
6 | 12780 |
7 | 238770 |
8 | 5281920 |
9 | 134946000 |
10 | 3909578400 |
11 | 126638542800 |
12 | 4535037460800 |
13 | 177904622095200 |
14 | 7586967310322400 |
15 | 349479111223242000 |
16 | 17292052928037888000 |
17 | 914673660594613920000 |
18 | 51506610632458293312000 |
19 | 3076341001739003430432000 |
[1,2,9,72,840,12780,238770,5281920,134946000, 3909578400,126638542800,4535037460800, 177904622095200,7586967310322400, 349479111223242000,17292052928037888000, 914673660594613920000,51506610632458293312000, 3076341001739003430432000] |