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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 17 |
| 3 | 120 |
| 4 | 1515 |
| 5 | 19449 |
| 6 | 166682 |
| 7 | 1730105 |
| 8 | 18344433 |
| 9 | 186996068 |
| 10 | 1929020093 |
| 11 | 20000798340 |
| 12 | 205893266832 |
| 13 | 2122824479646 |
| 14 | 21911879424345 |
| 15 | 226005819417517 |
| 16 | 2331282643796687 |
| 17 | 24051519818547252 |
| 18 | 248109780944578426 |
[1,17,120,1515,19449,166682,1730105,18344433, 186996068,1929020093,20000798340,205893266832, 2122824479646,21911879424345,226005819417517, 2331282643796687,24051519818547252, 248109780944578426] |