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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 17 |
| 3 | 309 |
| 4 | 3635 |
| 5 | 35870 |
| 6 | 346172 |
| 7 | 3128641 |
| 8 | 27439857 |
| 9 | 234322382 |
| 10 | 1959091067 |
| 11 | 16107499923 |
| 12 | 130573017760 |
| 13 | 1045978247546 |
| 14 | 8294049221347 |
| 15 | 65189007190923 |
| 16 | 508421219807214 |
| 17 | 3938274043202322 |
| 18 | 30321280493011911 |
| 19 | 232179051504428919 |
[1,17,309,3635,35870,346172,3128641,27439857, 234322382,1959091067,16107499923,130573017760, 1045978247546,8294049221347,65189007190923, 508421219807214,3938274043202322, 30321280493011911,232179051504428919] |