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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 8 |
| 3 | 168 |
| 4 | 6720 |
| 5 | 436800 |
| 6 | 41932800 |
| 7 | 5577062400 |
| 8 | 981562982400 |
| 9 | 220851671040000 |
| 10 | 61838467891200000 |
| 11 | 21086917550899200000 |
| 12 | 8603462360766873600000 |
| 13 | 4138265395528866201600000 |
| 14 | 2317428621496165072896000000 |
[1,1,8,168,6720,436800,41932800,5577062400, 981562982400,220851671040000,61838467891200000, 21086917550899200000,8603462360766873600000, 4138265395528866201600000, 2317428621496165072896000000] |