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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 4 |
| 3 | 128 |
| 4 | 186624 |
| 5 | 24461180928 |
| 6 | 477757440000000000 |
| 7 | 2079947912569159680000000000 |
| 8 | 2821337329257037336798707056640000000000 |
| 9 | 1588271718091057966534018222437593205367111680000000000 |
| 10 | 476782128558831092865939388401540382200008655926882902537666560000000000 |
[1,2,4,128,186624,24461180928,477757440000000000, 2079947912569159680000000000, 2821337329257037336798707056640000000000, 15882717180910579665340182224375932053671116800000\ 00000, 47678212855883109286593938840154038220000865592688\ 2902537666560000000000] |