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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 12 |
| 3 | 192 |
| 4 | 6480 |
| 5 | 179200 |
| 6 | 4410000 |
| 7 | 133402500 |
| 8 | 4249941696 |
| 9 | 122367445200 |
| 10 | 3480673996800 |
| 11 | 117643011932160 |
| 12 | 3659449159080000 |
| 13 | 106518477825760000 |
| 14 | 3521767173114190000 |
| 15 | 114708987924290760000 |
| 16 | 3525270042097046880000 |
| 17 | 110552468520163390156800 |
[1,12,192,6480,179200,4410000,133402500, 4249941696,122367445200,3480673996800, 117643011932160,3659449159080000, 106518477825760000,3521767173114190000, 114708987924290760000,3525270042097046880000, 110552468520163390156800] |