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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 17 |
| 2 | 133 |
| 3 | 857 |
| 4 | 6413 |
| 5 | 48867 |
| 6 | 381313 |
| 7 | 3016163 |
| 8 | 24107789 |
| 9 | 194175677 |
| 10 | 1573174523 |
| 11 | 12802874695 |
| 12 | 104553143825 |
| 13 | 856091328837 |
| 14 | 7024086050415 |
| 15 | 57721845597987 |
| 16 | 474910998928093 |
| 17 | 3910960204957435 |
| 18 | 32229946522723645 |
| 19 | 265747140536421765 |
[1,17,133,857,6413,48867,381313,3016163,24107789, 194175677,1573174523,12802874695,104553143825, 856091328837,7024086050415,57721845597987, 474910998928093,3910960204957435, 32229946522723645,265747140536421765] |