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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 2 |
| 6 | 0 |
| 7 | 1 |
| 8 | 20 |
| 9 | 20 |
| 10 | 1 |
| 11 | 6 |
| 12 | 117 |
| 13 | 266 |
| 14 | 117 |
| 15 | 6 |
| 16 | 21 |
| 17 | 503 |
| 18 | 1972 |
| 19 | 1972 |
| 20 | 503 |
| 21 | 21 |
| 22 | 56 |
| 23 | 1750 |
| 24 | 10784 |
| 25 | 19750 |
| 26 | 10784 |
| 27 | 1750 |
| 28 | 56 |
| 29 | 126 |
| 30 | 5209 |
| 31 | 48501 |
| 32 | 150085 |
| 33 | 150085 |
| 34 | 48501 |
| 35 | 5209 |
| 36 | 126 |
| 37 | 252 |
| 38 | 13751 |
| 39 | 189595 |
| 40 | 955347 |
| 41 | 1673658 |
| 42 | 955347 |
| 43 | 189595 |
| 44 | 13751 |
| 45 | 252 |
| 46 | 462 |
| 47 | 33000 |
[0,0,0,0,2,0,1,20,20,1,6,117,266,117,6,21,503, 1972,1972,503,21,56,1750,10784,19750,10784,1750, 56,126,5209,48501,150085,150085,48501,5209,126, 252,13751,189595,955347,1673658,955347,189595, 13751,252,462,33000] |