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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 7 |
| 3 | 45 |
| 4 | 650 |
| 5 | 24520 |
| 6 | 2625117 |
| 7 | 772423369 |
| 8 | 547602149421 |
| 9 | 799176231553933 |
[2,7,45,650,24520,2625117,772423369,547602149421, 799176231553933] |