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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 120 |
| 3 | 1980 |
| 4 | 7920 |
| 5 | 30240 |
| 6 | 109200 |
| 7 | 120120 |
| 8 | 480480 |
| 9 | 491400 |
| 10 | 1853280 |
| 11 | 1884960 |
| 12 | 1965600 |
| 13 | 2106720 |
| 14 | 7207200 |
| 15 | 8168160 |
| 16 | 8482320 |
| 17 | 8648640 |
| 18 | 31600800 |
| 19 | 121080960 |
| 20 | 122522400 |
| 21 | 129729600 |
| 22 | 136936800 |
| 23 | 465585120 |
| 24 | 490089600 |
| 25 | 497296800 |
| 26 | 514594080 |
| 27 | 537213600 |
| 28 | 551350800 |
[1,120,1980,7920,30240,109200,120120,480480, 491400,1853280,1884960,1965600,2106720,7207200, 8168160,8482320,8648640,31600800,121080960, 122522400,129729600,136936800,465585120,490089600, 497296800,514594080,537213600,551350800] |