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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 0 |
| 3 | 0 |
| 4 | 1 |
| 5 | 0 |
| 6 | 0 |
| 7 | 0 |
| 8 | 2 |
| 9 | 9 |
| 10 | 6 |
| 11 | 1 |
| 12 | 0 |
| 13 | 0 |
| 14 | 0 |
| 15 | 0 |
| 16 | 6 |
| 17 | 84 |
| 18 | 316 |
| 19 | 492 |
| 20 | 417 |
| 21 | 212 |
| 22 | 66 |
| 23 | 12 |
| 24 | 1 |
| 25 | 0 |
| 26 | 0 |
| 27 | 0 |
| 28 | 0 |
| 29 | 0 |
| 30 | 24 |
| 31 | 720 |
| 32 | 6440 |
| 33 | 26875 |
| 34 | 65280 |
| 35 | 105566 |
| 36 | 122580 |
| 37 | 106825 |
| 38 | 71700 |
| 39 | 37540 |
| 40 | 15344 |
| 41 | 4835 |
| 42 | 1140 |
| 43 | 190 |
| 44 | 20 |
| 45 | 1 |
| 46 | 0 |
| 47 | 0 |
| 48 | 0 |
| 49 | 0 |
| 50 | 0 |
| 51 | 0 |
| 52 | 120 |
| 53 | 6480 |
| 54 | 107850 |
| 55 | 868830 |
| 56 | 4188696 |
| 57 | 13715940 |
[1,0,0,1,0,0,0,2,9,6,1,0,0,0,0,6,84,316,492,417, 212,66,12,1,0,0,0,0,0,24,720,6440,26875,65280, 105566,122580,106825,71700,37540,15344,4835,1140, 190,20,1,0,0,0,0,0,0,120,6480,107850,868830, 4188696,13715940] |