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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 0 |
| 4 | 3 |
| 5 | 6 |
| 6 | 0 |
| 7 | 4 |
| 8 | 24 |
| 9 | 12 |
| 10 | 0 |
| 11 | 5 |
| 12 | 60 |
| 13 | 120 |
| 14 | 20 |
| 15 | 0 |
| 16 | 6 |
| 17 | 120 |
| 18 | 540 |
| 19 | 480 |
| 20 | 30 |
| 21 | 0 |
| 22 | 7 |
| 23 | 210 |
| 24 | 1680 |
| 25 | 3780 |
| 26 | 1680 |
| 27 | 42 |
| 28 | 0 |
| 29 | 8 |
| 30 | 336 |
| 31 | 4200 |
| 32 | 17920 |
| 33 | 22680 |
| 34 | 5376 |
| 35 | 56 |
| 36 | 0 |
| 37 | 9 |
| 38 | 504 |
| 39 | 9072 |
| 40 | 63000 |
| 41 | 161280 |
| 42 | 122472 |
| 43 | 16128 |
| 44 | 72 |
| 45 | 0 |
| 46 | 10 |
| 47 | 720 |
| 48 | 17640 |
| 49 | 181440 |
| 50 | 787500 |
| 51 | 1290240 |
| 52 | 612360 |
| 53 | 46080 |
| 54 | 90 |
| 55 | 0 |
[1,2,0,3,6,0,4,24,12,0,5,60,120,20,0,6,120,540, 480,30,0,7,210,1680,3780,1680,42,0,8,336,4200, 17920,22680,5376,56,0,9,504,9072,63000,161280, 122472,16128,72,0,10,720,17640,181440,787500, 1290240,612360,46080,90,0] |