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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 4 |
| 2 | 54 |
| 3 | 3682 |
| 4 | 1209830 |
| 5 | 1909172038 |
| 6 | 14441437270426 |
| 7 | 523308354987531254 |
| 8 | 90815542491916256949262 |
| 9 | 75466682574077698691682950866 |
| 10 | 300268405527350796472180876929042538 |
[1,4,54,3682,1209830,1909172038,14441437270426, 523308354987531254,90815542491916256949262, 75466682574077698691682950866, 300268405527350796472180876929042538] |