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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 144 |
| 4 | 4807526976 |
| 5 | 64202014863723094126901777428873111802307548623680 |
[1,3,144,4807526976, 64202014863723094126901777428873111802307548623680\ ] |