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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 24 |
| 4 | 316 |
| 5 | 6080 |
| 6 | 149824 |
| 7 | 5728896 |
| 8 | 259780608 |
| 9 | 14154310656 |
| 10 | 1054215834624 |
[1,3,24,316,6080,149824,5728896,259780608, 14154310656,1054215834624] |