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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 1 |
| 3 | 0 |
| 4 | -1 |
| 5 | 1 |
| 6 | 0 |
| 7 | 2 |
| 8 | -4 |
| 9 | 4 |
| 10 | -3 |
| 11 | 6 |
| 12 | -9 |
| 13 | 9 |
| 14 | -8 |
| 15 | 12 |
| 16 | -16 |
| 17 | 16 |
| 18 | -15 |
| 19 | 20 |
| 20 | -25 |
| 21 | 25 |
| 22 | -24 |
| 23 | 30 |
| 24 | -36 |
| 25 | 36 |
| 26 | -35 |
| 27 | 42 |
| 28 | -49 |
| 29 | 49 |
| 30 | -48 |
| 31 | 56 |
| 32 | -64 |
| 33 | 64 |
| 34 | -63 |
| 35 | 72 |
| 36 | -81 |
| 37 | 81 |
| 38 | -80 |
| 39 | 90 |
| 40 | -100 |
| 41 | 100 |
| 42 | -99 |
| 43 | 110 |
| 44 | -121 |
| 45 | 121 |
| 46 | -120 |
| 47 | 132 |
| 48 | -144 |
| 49 | 144 |
| 50 | -143 |
| 51 | 156 |
| 52 | -169 |
| 53 | 169 |
| 54 | -168 |
[0,0,1,0,-1,1,0,2,-4,4,-3,6,-9,9,-8,12,-16,16,-15, 20,-25,25,-24,30,-36,36,-35,42,-49,49,-48,56,-64, 64,-63,72,-81,81,-80,90,-100,100,-99,110,-121,121, -120,132,-144,144,-143,156,-169,169,-168] |