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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 24 |
| 5 | 120 |
| 6 | 720 |
| 7 | 5040 |
| 8 | 40320 |
| 9 | 181440 |
| 10 | 756000 |
| 11 | 3160080 |
| 12 | 13602600 |
| 13 | 60926580 |
| 14 | 285159966 |
| 15 | 1396646055 |
| 16 | 7158444465 |
| 17 | 35019420060 |
| 18 | 165994449732 |
| 19 | 774542703708 |
| 20 | 3596199290264 |
| 21 | 16729008975792 |
| 22 | 78297230499296 |
| 23 | 369560004222048 |
| 24 | 1760728654735744 |
| 25 | 8392003472443920 |
[1,1,2,6,24,120,720,5040,40320,181440,756000, 3160080,13602600,60926580,285159966,1396646055, 7158444465,35019420060,165994449732,774542703708, 3596199290264,16729008975792,78297230499296, 369560004222048,1760728654735744,8392003472443920] |