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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 4 |
| 3 | 3 |
| 4 | 80 |
| 5 | 1539 |
| 6 | 11459 |
| 7 | 848789 |
| 8 | 122310309 |
| 9 | 6602925250 |
| 10 | 2215354712154 |
[1,4,3,80,1539,11459,848789,122310309,6602925250, 2215354712154] |