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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 8 |
| 3 | 70 |
| 4 | 649 |
| 5 | 8379 |
| 6 | 124748 |
| 7 | 2237911 |
| 8 | 57942564 |
| 9 | 2226744922 |
| 10 | 121611666154 |
| 11 | 12022143900385 |
[1,8,70,649,8379,124748,2237911,57942564, 2226744922,121611666154,12022143900385] |