The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 48 |
| 5 | 240 |
| 6 | 34560 |
| 7 | 241920 |
| 8 | 92897280 |
| 9 | 15049359360 |
| 10 | 288947699712000 |
| 11 | 3178424696832000 |
| 12 | 3954468870810501120000 |
| 13 | 51408095320536514560000 |
| 14 | 232150733172291613910630400000 |
| 15 | 338475768965201173081699123200000000 |
| 16 | 3493719809197289292455451813740544000000000 |
[1,2,6,48,240,34560,241920,92897280,15049359360, 288947699712000,3178424696832000, 3954468870810501120000,51408095320536514560000, 232150733172291613910630400000, 338475768965201173081699123200000000, 3493719809197289292455451813740544000000000] |