The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 12 |
| 3 | 47520 |
| 4 | 266499072000 |
| 5 | 5578457158440714240000 |
| 6 | 903833169262981594760400076800000000 |
| 7 | 2035652583056655211566004660439314466655436800000000000 |
| 8 | 103962610930356904475854868257296244089884364267142052118842572800000000000000 |
[1,1,12,47520,266499072000,5578457158440714240000, 903833169262981594760400076800000000, 20356525830566552115660046604393144666554368000000\ 00000, 10396261093035690447585486825729624408988436426714\ 2052118842572800000000000000] |