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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 7 |
| 3 | 45 |
| 4 | 650 |
| 5 | 19286 |
| 6 | 1022736 |
| 7 | 86202115 |
| 8 | 10650429877 |
| 9 | 1821110552009 |
[2,7,45,650,19286,1022736,86202115,10650429877, 1821110552009] |