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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 324 |
| 5 | 300407 |
| 6 | 2572822729 |
| 7 | 18309814258048 |
| 8 | 2175521892821642304 |
[1,1,1,324,300407,2572822729,18309814258048, 2175521892821642304] |