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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 6 |
| 3 | 2 |
| 4 | 3 |
| 5 | 24 |
| 6 | 5 |
| 7 | 4 |
| 8 | 7 |
| 9 | 10 |
| 10 | 1080 |
| 11 | 35640 |
| 12 | 11 |
| 13 | 9 |
| 14 | 13 |
| 15 | 8 |
| 16 | 33 |
| 17 | 297600 |
| 18 | 17 |
| 19 | 588 |
| 20 | 19 |
| 21 | 20 |
| 22 | 1782 |
| 23 | 1907020800 |
| 24 | 23 |
| 25 | 216 |
| 26 | 45 |
| 27 | 34 |
| 28 | 78 |
[1,6,2,3,24,5,4,7,10,1080,35640,11,9,13,8,33, 297600,17,588,19,20,1782,1907020800,23,216,45,34, 78] |