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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 8 |
| 3 | 51 |
| 4 | 1015 |
| 5 | 30116 |
| 6 | 1929041 |
| 7 | 223336353 |
| 8 | 50789138692 |
| 9 | 21840171519903 |
| 10 | 18066655662899887 |
| 11 | 28530669418446423314 |
| 12 | 86301791696353013652605 |
[1,8,51,1015,30116,1929041,223336353,50789138692, 21840171519903,18066655662899887, 28530669418446423314,86301791696353013652605] |