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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 4 |
| 3 | 45 |
| 4 | 1041 |
| 5 | 41629 |
| 6 | 2582028 |
| 7 | 230689017 |
| 8 | 28145738365 |
| 9 | 4504704373961 |
| 10 | 916668654429870 |
| 11 | 231318743221265869 |
| 12 | 70928148561381638541 |
| 13 | 25983184166531408190165 |
| 14 | 11210928989636995091435576 |
[1,4,45,1041,41629,2582028,230689017,28145738365, 4504704373961,916668654429870,231318743221265869, 70928148561381638541,25983184166531408190165, 11210928989636995091435576] |