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| n | a(n) |
|---|---|
| 8 | 1 |
| 9 | 288 |
| 10 | 19560 |
| 11 | 921360 |
| 12 | 37423914 |
| 13 | 1124673264 |
| 14 | 34065856396 |
| 15 | 1010435626200 |
| 16 | 27564092244689 |
| 17 | 746494701977024 |
| 18 | 20568917530438368 |
| 19 | 575594436161070144 |
| 20 | 15985318079107792576 |
| 21 | 452561731064312392320 |
| 22 | 12942265817549110947520 |
| 23 | 383915932720263224659840 |
[1,288,19560,921360,37423914,1124673264, 34065856396,1010435626200,27564092244689, 746494701977024,20568917530438368, 575594436161070144,15985318079107792576, 452561731064312392320,12942265817549110947520, 383915932720263224659840] |