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| n | a(n) |
|---|---|
| 1 | 20 |
| 2 | 220 |
| 3 | 23932 |
| 4 | 2390065448 |
| 5 | 1320590620757744871288 |
| 6 | 51897350327827018479313921072100496772300552736 |
[20,220,23932,2390065448,1320590620757744871288, 51897350327827018479313921072100496772300552736] |