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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 6 |
| 3 | 126 |
| 4 | 12870 |
| 5 | 5200300 |
| 6 | 9075135300 |
| 7 | 63205303218876 |
| 8 | 1832624140942590534 |
| 9 | 212392290424395860814420 |
| 10 | 100891344545564193334812497256 |
| 11 | 191645966716130525165099506263706416 |
| 12 | 1480212998448786189993816895482588794876100 |
[1,1,6,126,12870,5200300,9075135300, 63205303218876,1832624140942590534, 212392290424395860814420, 100891344545564193334812497256, 191645966716130525165099506263706416, 1480212998448786189993816895482588794876100] |