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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 9 |
| 3 | 400 |
| 4 | 19456921 |
| 5 | 1101216948902114953248 |
| 6 | 76796373204229717290826972582321984854855228022915711475735049 |
[1,2,9,400,19456921,1101216948902114953248, 76796373204229717290826972582321984854855228022915\ 711475735049] |