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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 6 |
| 4 | 108 |
| 5 | 4320 |
| 6 | 324000 |
| 7 | 40824000 |
| 8 | 8001504000 |
| 9 | 2304433152000 |
| 10 | 933295426560000 |
| 11 | 513312484608000000 |
| 12 | 372664863825408000000 |
| 13 | 348814312540581888000000 |
| 14 | 412647331735508373504000000 |
| 15 | 606591577651197309050880000000 |
| 16 | 1091864839772155156291584000000000 |
| 17 | 2375897891344209620090486784000000000 |
[1,1,6,108,4320,324000,40824000,8001504000, 2304433152000,933295426560000,513312484608000000, 372664863825408000000,348814312540581888000000, 412647331735508373504000000, 606591577651197309050880000000, 1091864839772155156291584000000000, 2375897891344209620090486784000000000] |