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| n | a(n) |
|---|---|
| 2 | 1 |
| 3 | -1 |
| 4 | 1 |
| 5 | 3 |
| 6 | -1 |
| 7 | -3 |
| 8 | -10 |
| 9 | -15 |
| 10 | 1 |
| 11 | 3 |
| 12 | 10 |
| 13 | 30 |
| 14 | 55 |
| 15 | 105 |
| 16 | 105 |
| 17 | -1 |
| 18 | -3 |
| 19 | -10 |
| 20 | -30 |
| 21 | -76 |
| 22 | -168 |
| 23 | -350 |
| 24 | -630 |
| 25 | -910 |
| 26 | -1260 |
| 27 | -945 |
| 28 | 1 |
| 29 | 3 |
| 30 | 10 |
| 31 | 30 |
| 32 | 76 |
| 33 | 196 |
| 34 | 434 |
| 35 | 910 |
| 36 | 1806 |
| 37 | 3381 |
| 38 | 5789 |
| 39 | 9135 |
| 40 | 12880 |
| 41 | 15750 |
| 42 | 17325 |
| 43 | 10395 |
| 44 | -1 |
| 45 | -3 |
| 46 | -10 |
| 47 | -30 |
| 48 | -76 |
| 49 | -196 |
| 50 | -470 |
| 51 | -1018 |
| 52 | -2166 |
| 53 | -4461 |
| 54 | -8609 |
| 55 | -16065 |
| 56 | -28336 |
| 57 | -48006 |
| 58 | -78519 |
| 59 | -120960 |
| 60 | -172200 |
| 61 | -228375 |
| 62 | -275275 |
| 63 | -294525 |
| 64 | -270270 |
| 65 | -135135 |
[1,-1,1,3,-1,-3,-10,-15,1,3,10,30,55,105,105,-1, -3,-10,-30,-76,-168,-350,-630,-910,-1260,-945,1,3, 10,30,76,196,434,910,1806,3381,5789,9135,12880, 15750,17325,10395,-1,-3,-10,-30,-76,-196,-470, -1018,-2166,-4461,-8609,-16065,-28336,-48006, -78519,-120960,-172200,-228375,-275275,-294525, -270270,-135135] |