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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 2 |
| 3 | 0 |
| 4 | 3 |
| 5 | 3 |
| 6 | 0 |
| 7 | 4 |
| 8 | 6 |
| 9 | 4 |
| 10 | 0 |
| 11 | 5 |
| 12 | 10 |
| 13 | 10 |
| 14 | 5 |
| 15 | 0 |
| 16 | 6 |
| 17 | 15 |
| 18 | 20 |
| 19 | 15 |
| 20 | 6 |
| 21 | 0 |
| 22 | 7 |
| 23 | 21 |
| 24 | 35 |
| 25 | 35 |
| 26 | 21 |
| 27 | 7 |
| 28 | 0 |
| 29 | 8 |
| 30 | 28 |
| 31 | 56 |
| 32 | 70 |
| 33 | 56 |
| 34 | 28 |
| 35 | 8 |
| 36 | 0 |
| 37 | 9 |
| 38 | 36 |
| 39 | 84 |
| 40 | 126 |
| 41 | 126 |
| 42 | 84 |
| 43 | 36 |
| 44 | 9 |
| 45 | 0 |
| 46 | 10 |
| 47 | 45 |
| 48 | 120 |
| 49 | 210 |
| 50 | 252 |
| 51 | 210 |
| 52 | 120 |
| 53 | 45 |
| 54 | 10 |
| 55 | 0 |
| 56 | 11 |
| 57 | 55 |
| 58 | 165 |
| 59 | 330 |
| 60 | 462 |
[0,0,2,0,3,3,0,4,6,4,0,5,10,10,5,0,6,15,20,15,6,0, 7,21,35,35,21,7,0,8,28,56,70,56,28,8,0,9,36,84, 126,126,84,36,9,0,10,45,120,210,252,210,120,45,10, 0,11,55,165,330,462] |