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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 4 |
| 3 | 111 |
| 4 | 12600 |
| 5 | 5722258 |
| 6 | 10419647136 |
| 7 | 76124127132667 |
| 8 | 2234758718926030048 |
| 9 | 263964471372716219981614 |
| 10 | 125532541357451846737479404864 |
| 11 | 240382906462440786858510574342553910 |
| 12 | 1852958218856132372722626702327036659515008 |
[1,1,4,111,12600,5722258,10419647136, 76124127132667,2234758718926030048, 263964471372716219981614, 125532541357451846737479404864, 240382906462440786858510574342553910, 1852958218856132372722626702327036659515008] |