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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 1 |
| 7 | 1 |
| 8 | 1 |
| 9 | 17 |
| 10 | 17 |
| 11 | 57 |
| 12 | 57 |
| 13 | 317 |
| 14 | 317 |
| 15 | 3151 |
| 16 | 3151 |
| 17 | 61021 |
| 18 | 61021 |
| 19 | 1767277 |
| 20 | 1767277 |
| 21 | 57009275 |
| 22 | 57009275 |
[1,1,1,1,1,1,1,1,17,17,57,57,317,317,3151,3151, 61021,61021,1767277,1767277,57009275,57009275] |