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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 12 |
| 3 | 249 |
| 4 | 7744 |
| 5 | 401625 |
| 6 | 30080736 |
| 7 | 3034643689 |
| 8 | 371205076992 |
| 9 | 52680504366801 |
| 10 | 12762075858688000 |
| 11 | 4097222646625776921 |
| 12 | 1485034580150268715008 |
| 13 | 546325401769976582587561 |
| 14 | 203541885180568005538811904 |
| 15 | 89218786842877518275107415625 |
[1,1,12,249,7744,401625,30080736,3034643689, 371205076992,52680504366801,12762075858688000, 4097222646625776921,1485034580150268715008, 546325401769976582587561, 203541885180568005538811904, 89218786842877518275107415625] |