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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 4 |
| 3 | 36 |
| 4 | 144 |
| 5 | 3600 |
| 6 | 1200 |
| 7 | 58800 |
| 8 | 235200 |
| 9 | 6350400 |
| 10 | 6350400 |
| 11 | 768398400 |
| 12 | 768398400 |
| 13 | 129859329600 |
| 14 | 129859329600 |
| 15 | 129859329600 |
| 16 | 519437318400 |
| 17 | 150117385017600 |
| 18 | 50039128339200 |
| 19 | 18064125330451200 |
| 20 | 3612825066090240 |
| 21 | 3612825066090240 |
| 22 | 3612825066090240 |
| 23 | 1911184459961736960 |
[1,4,36,144,3600,1200,58800,235200,6350400, 6350400,768398400,768398400,129859329600, 129859329600,129859329600,519437318400, 150117385017600,50039128339200,18064125330451200, 3612825066090240,3612825066090240, 3612825066090240,1911184459961736960] |