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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 18 |
| 3 | 1008 |
| 4 | 282240 |
| 5 | 269982720 |
| 6 | 1209522585600 |
| 7 | 19170449172725760 |
| 8 | 1315623687226078003200 |
| 9 | 342810031916266844848128000 |
| 10 | 367173017574548024679647831654400 |
| 11 | 1534674653372294809728193910618770636800 |
| 12 | 26108462572660693961035262279317764270194688000 |
[1,18,1008,282240,269982720,1209522585600, 19170449172725760,1315623687226078003200, 342810031916266844848128000, 367173017574548024679647831654400, 1534674653372294809728193910618770636800, 26108462572660693961035262279317764270194688000] |