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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 | 3 |
| 11 | 7 |
| 12 | 13 |
| 13 | 21 |
| 14 | 43 |
| 15 | 105 |
| 16 | 255 |
| 17 | 713 |
| 18 | 2327 |
| 19 | 7879 |
| 20 | 28233 |
| 21 | 105483 |
| 22 | 441751 |
| 23 | 1976665 |
| 24 | 9809483 |
| 25 | 52365589 |
| 26 | 307831711 |
[1,1,1,1,1,1,1,1,1,3,7,13,21,43,105,255,713,2327, 7879,28233,105483,441751,1976665,9809483,52365589, 307831711] |