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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 2 |
| 3 | 8 |
| 4 | 12 |
| 5 | 64 |
| 6 | 120 |
| 7 | 768 |
| 8 | 1680 |
| 9 | 12288 |
| 10 | 30240 |
| 11 | 245760 |
| 12 | 665280 |
| 13 | 5898240 |
| 14 | 17297280 |
| 15 | 165150720 |
| 16 | 518918400 |
| 17 | 5284823040 |
| 18 | 17643225600 |
| 19 | 190253629440 |
| 20 | 670442572800 |
| 21 | 7610145177600 |
| 22 | 28158588057600 |
| 23 | 334846387814400 |
| 24 | 1295295050649600 |
[1,2,2,8,12,64,120,768,1680,12288,30240,245760, 665280,5898240,17297280,165150720,518918400, 5284823040,17643225600,190253629440,670442572800, 7610145177600,28158588057600,334846387814400, 1295295050649600] |