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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 1 |
| 7 | 2 |
| 8 | 2 |
| 9 | 5 |
| 10 | 11 |
| 11 | 25 |
| 12 | 51 |
| 13 | 136 |
| 14 | 367 |
| 15 | 886 |
| 16 | 2507 |
| 17 | 6986 |
| 18 | 20453 |
| 19 | 60708 |
| 20 | 172073 |
| 21 | 524771 |
| 22 | 1628140 |
| 23 | 5085497 |
[1,1,1,1,1,1,2,2,5,11,25,51,136,367,886,2507,6986, 20453,60708,172073,524771,1628140,5085497] |