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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 12 |
| 3 | 192 |
| 4 | 6480 |
| 5 | 179200 |
| 6 | 4410000 |
| 7 | 100590336 |
| 8 | 2175421248 |
| 9 | 45229916160 |
| 10 | 912328045200 |
| 11 | 17965673440000 |
| 12 | 346945899203904 |
| 13 | 6592659294154752 |
| 14 | 123580568462478400 |
| 15 | 2289795064260480000 |
| 16 | 42003815644116000000 |
[1,12,192,6480,179200,4410000,100590336, 2175421248,45229916160,912328045200, 17965673440000,346945899203904,6592659294154752, 123580568462478400,2289795064260480000, 42003815644116000000] |