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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 1 |
| 5 | 6 |
| 6 | 10 |
| 7 | 1 |
| 8 | 24 |
| 9 | 40 |
| 10 | 80 |
| 11 | 1 |
| 12 | 80 |
| 13 | 300 |
| 14 | 400 |
| 15 | 880 |
| 16 | 1 |
| 17 | 330 |
| 18 | 2400 |
| 19 | 3600 |
| 20 | 5280 |
| 21 | 12320 |
| 22 | 1 |
| 23 | 1302 |
| 24 | 15750 |
| 25 | 47600 |
| 26 | 55440 |
| 27 | 86240 |
| 28 | 209440 |
| 29 | 1 |
| 30 | 5936 |
| 31 | 129360 |
| 32 | 588000 |
| 33 | 837760 |
| 34 | 1034880 |
| 35 | 1675520 |
| 36 | 4188800 |
| 37 | 1 |
| 38 | 26784 |
| 39 | 1146040 |
| 40 | 5856480 |
[1,1,2,1,6,10,1,24,40,80,1,80,300,400,880,1,330, 2400,3600,5280,12320,1,1302,15750,47600,55440, 86240,209440,1,5936,129360,588000,837760,1034880, 1675520,4188800,1,26784,1146040,5856480] |