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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 120 |
| 4 | 255024 |
| 5 | 22869362880 |
| 6 | 136434451994755200 |
| 7 | 82262786502445667337542400 |
| 8 | 6980114960816118346901632738195814400 |
| 9 | 109099864394915605737486658299863377337267988480000 |
| 10 | 395935956167605557454071116707328675502625329271836386079338496000 |
[1,1,2,120,255024,22869362880,136434451994755200, 82262786502445667337542400, 6980114960816118346901632738195814400, 10909986439491560573748665829986337733726798848000\ 0, 39593595616760555745407111670732867550262532927183\ 6386079338496000] |