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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 120 |
| 4 | 151200 |
| 5 | 10897286400 |
| 6 | 70959641905152000 |
| 7 | 60493719168990845337600000 |
| 8 | 9226024969987629401488081551360000000 |
| 9 | 329646772667218349211759153151614073700352000000000 |
| 10 | 3498788402132461399351052923160966975192989707740695756800000000000 |
[1,1,3,120,151200,10897286400,70959641905152000, 60493719168990845337600000, 9226024969987629401488081551360000000, 32964677266721834921175915315161407370035200000000\ 0, 34987884021324613993510529231609669751929897077406\ 95756800000000000] |