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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 3 |
| 5 | 6 |
| 6 | 12 |
| 7 | 27 |
| 8 | 63 |
| 9 | 154 |
| 10 | 398 |
| 11 | 1055 |
| 12 | 2970 |
| 13 | 8503 |
| 14 | 25651 |
| 15 | 78483 |
| 16 | 250487 |
| 17 | 811802 |
| 18 | 2723130 |
| 19 | 9295483 |
| 20 | 32653552 |
| 21 | 116866283 |
| 22 | 428464743 |
| 23 | 1600474365 |
| 24 | 6102119282 |
| 25 | 23690388631 |
| 26 | 93631999867 |
| 27 | 376561553417 |
| 28 | 1538997717423 |
| 29 | 6395852269479 |
| 30 | 26978392034357 |
| 31 | 115628083386280 |
| 32 | 502520979828775 |
[1,1,2,3,6,12,27,63,154,398,1055,2970,8503,25651, 78483,250487,811802,2723130,9295483,32653552, 116866283,428464743,1600474365,6102119282, 23690388631,93631999867,376561553417, 1538997717423,6395852269479,26978392034357, 115628083386280,502520979828775] |