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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 6 |
| 4 | 5 |
| 5 | 72 |
| 6 | 60 |
| 7 | 18 |
| 8 | 7 |
| 9 | 660 |
| 10 | 556920 |
| 11 | 770 |
| 12 | 1008 |
| 13 | 985320 |
| 14 | 339660 |
| 15 | 34320 |
| 16 | 9 |
| 17 | 1670760 |
| 18 | 15300 |
| 19 | 61261200 |
| 20 | 1244880 |
| 21 | 6284880 |
| 22 | 3006556993440 |
| 23 | 199767760920 |
| 24 | 15048 |
| 25 | 26466884524080 |
| 26 | 61710920040 |
| 27 | 1163962800 |
| 28 | 3661447149360 |
| 29 | 50821170440040 |
| 30 | 205980334560 |
| 31 | 3262313854800 |
| 32 | 11 |
| 33 | 168473954880 |
[1,3,6,5,72,60,18,7,660,556920,770,1008,985320, 339660,34320,9,1670760,15300,61261200,1244880, 6284880,3006556993440,199767760920,15048, 26466884524080,61710920040,1163962800, 3661447149360,50821170440040,205980334560, 3262313854800,11,168473954880] |