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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 3 |
| 3 | 9 |
| 4 | 48 |
| 5 | 438 |
| 6 | 6774 |
| 7 | 178263 |
| 8 | 8064528 |
| 9 | 635233629 |
| 10 | 87635138366 |
| 11 | 20775026454364 |
| 12 | 8166374023036601 |
| 13 | 5000658352116041964 |
[2,3,9,48,438,6774,178263,8064528,635233629, 87635138366,20775026454364,8166374023036601, 5000658352116041964] |