The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 24 |
| 5 | 120 |
| 6 | 720 |
| 7 | 2952 |
| 8 | 16064 |
| 9 | 104800 |
| 10 | 816160 |
| 11 | 7327728 |
| 12 | 74031176 |
| 13 | 621684168 |
| 14 | 5950876288 |
| 15 | 64694543120 |
| 16 | 777746708096 |
[1,2,6,24,120,720,2952,16064,104800,816160, 7327728,74031176,621684168,5950876288,64694543120, 777746708096] |