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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 5 |
| 5 | 273 |
| 6 | 2982616 |
| 7 | 1830034134296583 |
| 8 | 4219771415190209120329546223112205 |
| 9 | 159545978336249166974717516821935499136450045008874233960892835107904996 |
[1,1,1,5,273,2982616,1830034134296583, 4219771415190209120329546223112205, 15954597833624916697471751682193549913645004500887\ 4233960892835107904996] |