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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 192 |
| 4 | 11784471548 |
| 5 | 49119584729121300101049137845273511977280 |
[1,1,2,192,11784471548, 49119584729121300101049137845273511977280] |