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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 11 |
| 4 | 61 |
| 5 | 407 |
| 6 | 3232 |
| 7 | 25093 |
| 8 | 211519 |
| 9 | 1745873 |
| 10 | 15637681 |
| 11 | 135802469 |
| 12 | 1224719101 |
| 13 | 11101010101 |
| 14 | 102829245283 |
| 15 | 929203539823 |
| 16 | 8708547008547 |
| 17 | 80952373015873 |
| 18 | 753731343283582 |
| 19 | 7074829931292517 |
[1,2,11,61,407,3232,25093,211519,1745873,15637681, 135802469,1224719101,11101010101,102829245283, 929203539823,8708547008547,80952373015873, 753731343283582,7074829931292517] |