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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 0 |
| 7 | 2 |
| 8 | 0 |
| 9 | 0 |
| 10 | 0 |
| 11 | 0 |
| 12 | 6 |
| 13 | 36 |
| 14 | 24 |
| 15 | 0 |
| 16 | 0 |
| 17 | 0 |
| 18 | 0 |
| 19 | 0 |
| 20 | 24 |
| 21 | 480 |
| 22 | 1940 |
| 23 | 2970 |
| 24 | 2040 |
| 25 | 544 |
| 26 | 0 |
| 27 | 0 |
| 28 | 0 |
| 29 | 0 |
| 30 | 0 |
| 31 | 0 |
| 32 | 120 |
| 33 | 5040 |
| 34 | 51330 |
| 35 | 221910 |
| 36 | 527940 |
| 37 | 772080 |
| 38 | 722250 |
| 39 | 426420 |
| 40 | 146160 |
| 41 | 22320 |
| 42 | 0 |
| 43 | 0 |
| 44 | 0 |
| 45 | 0 |
| 46 | 0 |
| 47 | 0 |
| 48 | 0 |
| 49 | 720 |
| 50 | 52920 |
| 51 | 1026060 |
| 52 | 8810970 |
| 53 | 43268442 |
| 54 | 138984510 |
[1,0,0,0,0,0,2,0,0,0,0,6,36,24,0,0,0,0,0,24,480, 1940,2970,2040,544,0,0,0,0,0,0,120,5040,51330, 221910,527940,772080,722250,426420,146160,22320,0, 0,0,0,0,0,0,720,52920,1026060,8810970,43268442, 138984510] |