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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 1 |
| 7 | 1 |
| 8 | 1 |
| 9 | 1 |
| 10 | 0 |
| 11 | -5 |
| 12 | -20 |
| 13 | -55 |
| 14 | -125 |
| 15 | -251 |
| 16 | -461 |
| 17 | -791 |
| 18 | -1286 |
| 19 | -2001 |
| 20 | -3001 |
| 21 | -4356 |
| 22 | -6121 |
| 23 | -8281 |
| 24 | -10626 |
| 25 | -12500 |
| 26 | -12340 |
| 27 | -6885 |
| 28 | 10110 |
| 29 | 49875 |
| 30 | 131626 |
| 31 | 286921 |
| 32 | 565781 |
| 33 | 1044971 |
| 34 | 1838626 |
| 35 | 3110751 |
| 36 | 5087561 |
| 37 | 8064366 |
| 38 | 12395461 |
| 39 | 18444251 |
| 40 | 26451625 |
| 41 | 36249035 |
| 42 | 46692715 |
| 43 | 54618710 |
[1,1,1,1,1,1,1,1,1,1,0,-5,-20,-55,-125,-251,-461, -791,-1286,-2001,-3001,-4356,-6121,-8281,-10626, -12500,-12340,-6885,10110,49875,131626,286921, 565781,1044971,1838626,3110751,5087561,8064366, 12395461,18444251,26451625,36249035,46692715, 54618710] |