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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 0 |
| 3 | 1 |
| 4 | 1 |
| 5 | 2 |
| 6 | 1 |
| 7 | 2 |
| 8 | 3 |
| 9 | 6 |
| 10 | 8 |
| 11 | 6 |
| 12 | 10 |
| 13 | 15 |
| 14 | 15 |
| 15 | 10 |
| 16 | 50 |
| 17 | 60 |
| 18 | 45 |
| 19 | 20 |
| 20 | 105 |
| 21 | 140 |
| 22 | 126 |
| 23 | 84 |
| 24 | 35 |
| 25 | 490 |
| 26 | 560 |
| 27 | 420 |
| 28 | 224 |
| 29 | 70 |
| 30 | 1176 |
| 31 | 1470 |
| 32 | 1260 |
| 33 | 840 |
| 34 | 420 |
| 35 | 126 |
| 36 | 5292 |
| 37 | 5880 |
| 38 | 4410 |
| 39 | 2520 |
| 40 | 1050 |
| 41 | 252 |
| 42 | 13860 |
| 43 | 16632 |
| 44 | 13860 |
| 45 | 9240 |
| 46 | 4950 |
| 47 | 1980 |
| 48 | 462 |
| 49 | 60984 |
| 50 | 66528 |
| 51 | 49896 |
| 52 | 29568 |
| 53 | 13860 |
| 54 | 4752 |
| 55 | 924 |
[1,0,1,1,2,1,2,3,6,8,6,10,15,15,10,50,60,45,20, 105,140,126,84,35,490,560,420,224,70,1176,1470, 1260,840,420,126,5292,5880,4410,2520,1050,252, 13860,16632,13860,9240,4950,1980,462,60984,66528, 49896,29568,13860,4752,924] |