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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 1 |
| 7 | 1 |
| 8 | 1 |
| 9 | 2 |
| 10 | 3 |
| 11 | 5 |
| 12 | 9 |
| 13 | 15 |
| 14 | 23 |
| 15 | 50 |
| 16 | 117 |
| 17 | 289 |
| 18 | 741 |
| 19 | 2046 |
| 20 | 5466 |
| 21 | 16079 |
| 22 | 52199 |
| 23 | 188773 |
| 24 | 719705 |
| 25 | 3000618 |
[1,1,1,1,1,1,1,1,2,3,5,9,15,23,50,117,289,741, 2046,5466,16079,52199,188773,719705,3000618] |