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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 3 |
| 4 | 3 |
| 5 | 11 |
| 6 | 61 |
| 7 | 601 |
| 8 | 601 |
| 9 | 2881 |
| 10 | 20867 |
| 11 | 286065 |
| 12 | 2821431 |
| 13 | 45564697 |
| 14 | 775615705 |
| 15 | 16612433139 |
| 16 | 16612433139 |
| 17 | 116158938203 |
| 18 | 1150638257617 |
| 19 | 23090252128971 |
| 20 | 299243344044281 |
| 21 | 6870621769276771 |
| 22 | 164016991433619495 |
| 23 | 5064921427930587339 |
| 24 | 86249855741531767869 |
[1,1,1,3,3,11,61,601,601,2881,20867,286065, 2821431,45564697,775615705,16612433139, 16612433139,116158938203,1150638257617, 23090252128971,299243344044281,6870621769276771, 164016991433619495,5064921427930587339, 86249855741531767869] |