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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 12 |
| 2 | 44 |
| 3 | 704 |
| 4 | 73920 |
| 5 | 320320 |
| 6 | 9929920 |
| 7 | 89369280 |
| 8 | 3664140480 |
| 9 | 84275231040 |
| 10 | 1432678927680 |
| 11 | 1432678927680 |
| 12 | 87393414588480 |
| 13 | 87393414588480 |
| 14 | 6204932435782080 |
| 15 | 14736714534982440 |
| 16 | 132630430814841960 |
| 17 | 5703108525038204280 |
| 18 | 5703108525038204280 |
| 19 | 18249947280122253696 |
| 20 | 1843244675292347623296 |
[1,12,44,704,73920,320320,9929920,89369280, 3664140480,84275231040,1432678927680, 1432678927680,87393414588480,87393414588480, 6204932435782080,14736714534982440, 132630430814841960,5703108525038204280, 5703108525038204280,18249947280122253696, 1843244675292347623296] |