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| n | a(n) |
|---|---|
| 1 | 8 |
| 2 | 55 |
| 3 | 490 |
| 4 | 3567 |
| 5 | 28925 |
| 6 | 223356 |
| 7 | 1759250 |
| 8 | 13750304 |
| 9 | 107777857 |
| 10 | 843913133 |
| 11 | 6610346674 |
| 12 | 51772001513 |
| 13 | 405494413096 |
| 14 | 3175909815583 |
| 15 | 24874462255642 |
| 16 | 194822212724279 |
| 17 | 1525890963999701 |
| 18 | 11951115491689468 |
| 19 | 93603785927597586 |
[8,55,490,3567,28925,223356,1759250,13750304, 107777857,843913133,6610346674,51772001513, 405494413096,3175909815583,24874462255642, 194822212724279,1525890963999701, 11951115491689468,93603785927597586] |