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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 8 |
| 3 | 42 |
| 4 | 374 |
| 5 | 3910 |
| 6 | 57210 |
| 7 | 960806 |
| 8 | 19261858 |
| 9 | 435877581 |
| 10 | 11123320196 |
| 11 | 313842837682 |
| 12 | 9729290348244 |
| 13 | 328114698808286 |
| 14 | 11967567841654606 |
| 15 | 469172063576559644 |
| 16 | 19676848703371278522 |
| 17 | 878942778254232811954 |
| 18 | 41661071646298278566886 |
| 19 | 2088331858752553232964218 |
[1,8,42,374,3910,57210,960806,19261858,435877581, 11123320196,313842837682,9729290348244, 328114698808286,11967567841654606, 469172063576559644,19676848703371278522, 878942778254232811954,41661071646298278566886, 2088331858752553232964218] |