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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 1 |
| 7 | 1 |
| 8 | 1 |
| 9 | 1 |
| 10 | 1 |
| 11 | 9 |
| 12 | 9 |
| 13 | 29 |
| 14 | 29 |
| 15 | 109 |
| 16 | 109 |
| 17 | 573 |
| 18 | 573 |
| 19 | 4463 |
| 20 | 4463 |
| 21 | 53751 |
| 22 | 53751 |
| 23 | 903115 |
| 24 | 903115 |
| 25 | 18601177 |
[1,1,1,1,1,1,1,1,1,1,9,9,29,29,109,109,573,573, 4463,4463,53751,53751,903115,903115,18601177] |