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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 46 |
| 4 | 1224 |
| 5 | 110185 |
| 6 | 26941396 |
| 7 | 17171750212 |
| 8 | 31199983979828 |
| 9 | 152008946406877474 |
[1,2,46,1224,110185,26941396,17171750212, 31199983979828,152008946406877474] |