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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 1 |
| 7 | 1 |
| 8 | 1 |
| 9 | 11 |
| 10 | 15 |
| 11 | 183 |
| 12 | 305 |
| 13 | 1851 |
| 14 | 3761 |
| 15 | 35145 |
| 16 | 75363 |
| 17 | 1670651 |
| 18 | 4265463 |
| 19 | 180681913 |
| 20 | 541465905 |
| 21 | 30900571055 |
| 22 | 107421245147 |
| 23 | 8457236647761 |
| 24 | 34044967457309 |
| 25 | 4310491231691799 |
[1,1,1,1,1,1,1,1,11,15,183,305,1851,3761,35145, 75363,1670651,4265463,180681913,541465905, 30900571055,107421245147,8457236647761, 34044967457309,4310491231691799] |