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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 3 |
| 3 | 9 |
| 4 | 99 |
| 5 | 353529 |
| 6 | 274407373885532679 |
| 7 | 2443417474326613595267894539584266773823049253134356679026035220285823429 |
[0,1,3,9,99,353529,274407373885532679, 24434174743266135952678945395842667738230492531343\ 56679026035220285823429] |