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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 33 |
| 3 | 195 |
| 4 | 2023 |
| 5 | 16839 |
| 6 | 151817 |
| 7 | 1328849 |
| 8 | 11758369 |
| 9 | 103628653 |
| 10 | 914646205 |
| 11 | 8068452381 |
| 12 | 71189251649 |
| 13 | 628067760289 |
| 14 | 5541284098945 |
| 15 | 48888866203241 |
| 16 | 431331449340441 |
| 17 | 3805499681885145 |
| 18 | 33574725778806817 |
| 19 | 296219181642118401 |
| 20 | 2613448287490035073 |
[1,1,33,195,2023,16839,151817,1328849,11758369, 103628653,914646205,8068452381,71189251649, 628067760289,5541284098945,48888866203241, 431331449340441,3805499681885145, 33574725778806817,296219181642118401, 2613448287490035073] |