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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 8 |
| 3 | 70 |
| 4 | 649 |
| 5 | 8368 |
| 6 | 123258 |
| 7 | 2207509 |
| 8 | 56481101 |
| 9 | 2090883077 |
| 10 | 106695657776 |
| 11 | 7917434629718 |
[1,8,70,649,8368,123258,2207509,56481101, 2090883077,106695657776,7917434629718] |