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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 7 |
| 4 | 175 |
| 5 | 27267 |
| 6 | 23663523 |
| 7 | 122092290831 |
| 8 | 3806404472713603 |
| 9 | 731708552185212577507 |
[1,1,7,175,27267,23663523,122092290831, 3806404472713603,731708552185212577507] |