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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 3 |
| 4 | 4 |
| 5 | 30 |
| 6 | 30 |
| 7 | 84 |
| 8 | 120 |
| 9 | 1260 |
| 10 | 840 |
| 11 | 13860 |
| 12 | 13860 |
| 13 | 180180 |
| 14 | 180180 |
| 15 | 180180 |
| 16 | 240240 |
| 17 | 6126120 |
| 18 | 6126120 |
| 19 | 116396280 |
| 20 | 58198140 |
| 21 | 116396280 |
| 22 | 116396280 |
| 23 | 2677114440 |
| 24 | 2677114440 |
| 25 | 13385572200 |
| 26 | 13385572200 |
| 27 | 40156716600 |
| 28 | 40156716600 |
| 29 | 776363187600 |
| 30 | 776363187600 |
[1,1,1,3,4,30,30,84,120,1260,840,13860,13860, 180180,180180,180180,240240,6126120,6126120, 116396280,58198140,116396280,116396280,2677114440, 2677114440,13385572200,13385572200,40156716600, 40156716600,776363187600,776363187600] |