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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 6 |
| 3 | 30 |
| 4 | 210 |
| 5 | 420 |
| 6 | 1260 |
| 7 | 13860 |
| 8 | 13860 |
| 9 | 180180 |
| 10 | 180180 |
| 11 | 360360 |
| 12 | 6126120 |
| 13 | 116396280 |
| 14 | 23279256 |
| 15 | 23279256 |
| 16 | 535422888 |
| 17 | 535422888 |
| 18 | 13385572200 |
| 19 | 40156716600 |
| 20 | 40156716600 |
| 21 | 1164544781400 |
| 22 | 36100888223400 |
| 23 | 72201776446800 |
| 24 | 72201776446800 |
[1,3,6,30,210,420,1260,13860,13860,180180,180180, 360360,6126120,116396280,23279256,23279256, 535422888,535422888,13385572200,40156716600, 40156716600,1164544781400,36100888223400, 72201776446800,72201776446800] |