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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 12 |
| 4 | 224 |
| 5 | 13440 |
| 6 | 2666496 |
| 7 | 1791885312 |
| 8 | 4161269661696 |
| 9 | 33955960439439360 |
| 10 | 987107315743488737280 |
| 11 | 103404624282172311371513856 |
| 12 | 39408968779516596852827017445376 |
| 13 | 55084280201257118417007491904448757760 |
| 14 | 284322478318511376197290687371005495020093440 |
[1,2,12,224,13440,2666496,1791885312, 4161269661696,33955960439439360, 987107315743488737280,103404624282172311371513856, 39408968779516596852827017445376, 55084280201257118417007491904448757760, 284322478318511376197290687371005495020093440] |