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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | -1 |
| 2 | 1 |
| 3 | -1 |
| 4 | 1 |
| 5 | -1 |
| 6 | 1 |
| 7 | -1 |
| 8 | 2 |
| 9 | -3 |
| 10 | 4 |
| 11 | -5 |
| 12 | 6 |
| 13 | -7 |
| 14 | 8 |
| 15 | -10 |
| 16 | 13 |
| 17 | -17 |
| 18 | 22 |
| 19 | -28 |
| 20 | 35 |
| 21 | -43 |
| 22 | 53 |
| 23 | -66 |
| 24 | 83 |
| 25 | -105 |
| 26 | 133 |
| 27 | -168 |
| 28 | 211 |
| 29 | -264 |
| 30 | 330 |
| 31 | -413 |
| 32 | 518 |
| 33 | -651 |
| 34 | 819 |
| 35 | -1030 |
| 36 | 1294 |
| 37 | -1624 |
| 38 | 2037 |
| 39 | -2555 |
| 40 | 3206 |
| 41 | -4025 |
| 42 | 5055 |
| 43 | -6349 |
| 44 | 7973 |
| 45 | -10010 |
| 46 | 12565 |
| 47 | -15771 |
| 48 | 19796 |
| 49 | -24851 |
| 50 | 31200 |
| 51 | -39173 |
| 52 | 49183 |
| 53 | -61748 |
| 54 | 77519 |
| 55 | -97315 |
| 56 | 122166 |
[1,-1,1,-1,1,-1,1,-1,2,-3,4,-5,6,-7,8,-10,13,-17, 22,-28,35,-43,53,-66,83,-105,133,-168,211,-264, 330,-413,518,-651,819,-1030,1294,-1624,2037,-2555, 3206,-4025,5055,-6349,7973,-10010,12565,-15771, 19796,-24851,31200,-39173,49183,-61748,77519, -97315,122166] |