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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 | 49 |
| 12 | 49 |
| 13 | 205 |
| 14 | 205 |
| 15 | 3001 |
| 16 | 3001 |
| 17 | 66003 |
| 18 | 66003 |
| 19 | 1489297 |
| 20 | 1489297 |
| 21 | 39955495 |
| 22 | 39955495 |
[1,1,1,1,1,1,1,1,17,17,49,49,205,205,3001,3001, 66003,66003,1489297,1489297,39955495,39955495] |