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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 6 |
| 5 | 2 |
| 6 | 5 |
| 7 | 360 |
| 8 | 2520 |
| 9 | 1680 |
| 10 | 15120 |
| 11 | 2700 |
| 12 | 11880 |
| 13 | 9979200 |
| 14 | 8648640 |
| 15 | 18345600 |
| 16 | 2476656000 |
| 17 | 27243216000 |
| 18 | 714714000 |
| 19 | 427508928000 |
| 20 | 1160381376000 |
| 21 | 1055947052160000 |
| 22 | 22174888095360000 |
| 23 | 38718058579200 |
| 24 | 141031842336000 |
[1,1,2,6,2,5,360,2520,1680,15120,2700,11880, 9979200,8648640,18345600,2476656000,27243216000, 714714000,427508928000,1160381376000, 1055947052160000,22174888095360000,38718058579200, 141031842336000] |