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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 2 |
| 6 | 4 |
| 7 | 1 |
| 8 | 3 |
| 9 | 11 |
| 10 | 37 |
| 11 | 1 |
| 12 | 4 |
| 13 | 21 |
| 14 | 122 |
| 15 | 621 |
| 16 | 1 |
| 17 | 5 |
| 18 | 34 |
| 19 | 273 |
| 20 | 2302 |
| 21 | 16526 |
| 22 | 1 |
| 23 | 6 |
| 24 | 50 |
| 25 | 508 |
| 26 | 2763 |
| 27 | 66482 |
| 28 | 640207 |
[1,1,1,1,2,4,1,3,11,37,1,4,21,122,621,1,5,34,273, 2302,16526,1,6,50,508,2763,66482,640207] |