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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 8 |
| 5 | 56 |
| 6 | 5152 |
| 7 | 17181920 |
| 8 | 479839479840 |
| 9 | 552587148319552587148320 |
| 10 | 370210294386175240152319370210294386175240152320 |
[1,2,4,8,56,5152,17181920,479839479840, 552587148319552587148320, 370210294386175240152319370210294386175240152320] |