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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 12 |
| 4 | 24 |
| 5 | 720 |
| 6 | 720 |
| 7 | 151200 |
| 8 | 302400 |
| 9 | 1814400 |
| 10 | 1814400 |
| 11 | 4191264000 |
| 12 | 4191264000 |
| 13 | 125863657920000 |
| 14 | 125863657920000 |
| 15 | 125863657920000 |
| 16 | 251727315840000 |
| 17 | 128509312009478400000 |
| 18 | 128509312009478400000 |
| 19 | 1246500488605217541696000000 |
[1,2,12,24,720,720,151200,302400,1814400,1814400, 4191264000,4191264000,125863657920000, 125863657920000,125863657920000,251727315840000, 128509312009478400000,128509312009478400000, 1246500488605217541696000000] |