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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 5 |
| 3 | 67 |
| 4 | 3569 |
| 5 | 545364 |
| 6 | 273369257 |
| 7 | 449467029436 |
| 8 | 2390166008989465 |
[1,5,67,3569,545364,273369257,449467029436, 2390166008989465] |