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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 3 |
| 3 | 4 |
| 4 | 6 |
| 5 | 8 |
| 6 | 19 |
| 7 | 44 |
| 8 | 314 |
| 9 | 7526 |
| 10 | 846993 |
| 11 | 324127860 |
| 12 | 403254094632 |
| 13 | 1555631972009430 |
| 14 | 19731915624463099553 |
| 15 | 791773335030637885025288 |
| 16 | 107432353216118868234728540268 |
| 17 | 47049030539260648478475949282317452 |
| 18 | 71364337698829887974206671525372672234855 |
[1,2,3,4,6,8,19,44,314,7526,846993,324127860, 403254094632,1555631972009430, 19731915624463099553,791773335030637885025288, 107432353216118868234728540268, 47049030539260648478475949282317452, 71364337698829887974206671525372672234855] |