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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 144 |
| 3 | 64800 |
| 4 | 101606400 |
| 5 | 411505920000 |
| 6 | 3585039575040000 |
| 7 | 59375425441812480000 |
| 8 | 1710012252724199424000000 |
| 9 | 80059353648041568632832000000 |
| 10 | 5780285333388601255290470400000000 |
| 11 | 616883611349898303167109582028800000000 |
| 12 | 93983451956379706284115479041251737600000000 |
[1,2,144,64800,101606400,411505920000, 3585039575040000,59375425441812480000, 1710012252724199424000000, 80059353648041568632832000000, 5780285333388601255290470400000000, 616883611349898303167109582028800000000, 93983451956379706284115479041251737600000000] |