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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 12 |
| 3 | 488 |
| 4 | 481776 |
| 5 | 157549032992 |
| 6 | 4059976627283664056256 |
| 7 | 524253448460177960474729517490503566696576 |
[1,2,12,488,481776,157549032992, 4059976627283664056256, 524253448460177960474729517490503566696576] |