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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 11 |
| 3 | 101 |
| 4 | 851 |
| 5 | 6885 |
| 6 | 54723 |
| 7 | 432021 |
| 8 | 3403859 |
| 9 | 26811397 |
| 10 | 211225187 |
| 11 | 1664405621 |
| 12 | 13116776819 |
| 13 | 103376383461 |
| 14 | 814752361347 |
| 15 | 6421443995733 |
| 16 | 50610420076691 |
| 17 | 398884119723973 |
| 18 | 3143787312038051 |
| 19 | 24777605586822197 |
| 20 | 195283435452156851 |
[1,11,101,851,6885,54723,432021,3403859,26811397, 211225187,1664405621,13116776819,103376383461, 814752361347,6421443995733,50610420076691, 398884119723973,3143787312038051, 24777605586822197,195283435452156851] |