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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | -1 |
| 3 | 0 |
| 4 | -1 |
| 5 | 2 |
| 6 | -1 |
| 7 | 0 |
| 8 | 0 |
| 9 | 0 |
| 10 | -1 |
| 11 | 4 |
| 12 | -6 |
| 13 | 6 |
| 14 | -11 |
| 15 | 20 |
| 16 | -21 |
| 17 | 16 |
| 18 | -17 |
| 19 | 20 |
| 20 | -15 |
| 21 | 6 |
| 22 | -1 |
| 23 | 0 |
| 24 | 0 |
| 25 | 0 |
| 26 | 0 |
| 27 | 0 |
| 28 | -1 |
| 29 | 10 |
| 30 | -45 |
| 31 | 124 |
| 32 | -254 |
| 33 | 472 |
| 34 | -876 |
| 35 | 1512 |
| 36 | -2289 |
| 37 | 3184 |
| 38 | -4369 |
| 39 | 5880 |
| 40 | -7491 |
| 41 | 9240 |
| 42 | -11697 |
| 43 | 15640 |
| 44 | -22003 |
| 45 | 31916 |
| 46 | -46450 |
| 47 | 67104 |
| 48 | -96081 |
| 49 | 133976 |
| 50 | -178209 |
| 51 | 226608 |
[1,-1,0,-1,2,-1,0,0,0,-1,4,-6,6,-11,20,-21,16,-17, 20,-15,6,-1,0,0,0,0,0,-1,10,-45,124,-254,472,-876, 1512,-2289,3184,-4369,5880,-7491,9240,-11697, 15640,-22003,31916,-46450,67104,-96081,133976, -178209,226608] |