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 | 4704 |
| 8 | 34440 |
| 9 | 277248 |
| 10 | 2432592 |
| 11 | 24309224 |
| 12 | 260433682 |
| 13 | 3042046372 |
| 14 | 37591396676 |
| 15 | 495967203570 |
| 16 | 7110282029252 |
[1,2,6,24,120,720,4704,34440,277248,2432592, 24309224,260433682,3042046372,37591396676, 495967203570,7110282029252] |