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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 1 |
| 7 | 3 |
| 8 | 9 |
| 9 | 21 |
| 10 | 41 |
| 11 | 85 |
| 12 | 247 |
| 13 | 661 |
| 14 | 2133 |
| 15 | 7669 |
| 16 | 30043 |
| 17 | 131633 |
| 18 | 623713 |
| 19 | 3176911 |
| 20 | 18218893 |
| 21 | 109622217 |
| 22 | 754540743 |
| 23 | 5491953507 |
| 24 | 45422445535 |
[1,1,1,1,1,1,3,9,21,41,85,247,661,2133,7669,30043, 131633,623713,3176911,18218893,109622217, 754540743,5491953507,45422445535] |