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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 1 |
| 5 | 1 |
| 6 | -1 |
| 7 | -4 |
| 8 | -4 |
| 9 | 5 |
| 10 | 9 |
| 11 | 9 |
| 12 | -14 |
| 13 | -16 |
| 14 | -16 |
| 15 | 30 |
| 16 | 25 |
| 17 | 25 |
| 18 | -55 |
| 19 | -36 |
| 20 | -36 |
| 21 | 91 |
| 22 | 49 |
| 23 | 49 |
| 24 | -140 |
| 25 | -64 |
| 26 | -64 |
| 27 | 204 |
| 28 | 81 |
| 29 | 81 |
| 30 | -285 |
| 31 | -100 |
| 32 | -100 |
| 33 | 385 |
| 34 | 121 |
| 35 | 121 |
| 36 | -506 |
| 37 | -144 |
| 38 | -144 |
| 39 | 650 |
| 40 | 169 |
| 41 | 169 |
| 42 | -819 |
| 43 | -196 |
| 44 | -196 |
| 45 | 1015 |
| 46 | 225 |
| 47 | 225 |
| 48 | -1240 |
| 49 | -256 |
| 50 | -256 |
[0,0,0,0,1,1,-1,-4,-4,5,9,9,-14,-16,-16,30,25,25, -55,-36,-36,91,49,49,-140,-64,-64,204,81,81,-285, -100,-100,385,121,121,-506,-144,-144,650,169,169, -819,-196,-196,1015,225,225,-1240,-256,-256] |