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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 1 |
| 7 | 1 |
| 8 | 3 |
| 9 | 7 |
| 10 | 13 |
| 11 | 21 |
| 12 | 39 |
| 13 | 135 |
| 14 | 491 |
| 15 | 1711 |
| 16 | 5531 |
| 17 | 18851 |
| 18 | 87961 |
| 19 | 493635 |
| 20 | 2869867 |
| 21 | 17154745 |
| 22 | 107225849 |
| 23 | 792577759 |
| 24 | 6869876861 |
| 25 | 66058401395 |
| 26 | 676488427499 |
| 27 | 7479488157903 |
| 28 | 92053084127249 |
| 29 | 1298331132850519 |
| 30 | 20359043284485661 |
[1,1,1,1,1,1,1,3,7,13,21,39,135,491,1711,5531, 18851,87961,493635,2869867,17154745,107225849, 792577759,6869876861,66058401395,676488427499, 7479488157903,92053084127249,1298331132850519, 20359043284485661] |