| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 12 |
| 3 | 448 |
| 4 | 61440 |
| 5 | 32505856 |
| 6 | 67645734912 |
| 7 | 558551906910208 |
| 8 | 18374686479671623680 |
| 9 | 2413129272746388704198656 |
| 10 | 1266412660188944021221804081152 |
| 11 | 2657157917355198038900481496478384128 |
| 12 | 22295300680659888126120304278929453214597120 |
[0,1,12,448,61440,32505856,67645734912, 558551906910208,18374686479671623680, 2413129272746388704198656, 1266412660188944021221804081152, 2657157917355198038900481496478384128, 22295300680659888126120304278929453214597120] |