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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | -1 |
| 4 | 3 |
| 5 | -3 |
| 6 | 0 |
| 7 | 4 |
| 8 | -6 |
| 9 | 0 |
| 10 | 1 |
| 11 | 5 |
| 12 | -10 |
| 13 | 0 |
| 14 | 5 |
| 15 | 0 |
| 16 | 6 |
| 17 | -15 |
| 18 | 0 |
| 19 | 15 |
| 20 | 0 |
| 21 | -3 |
| 22 | 7 |
| 23 | -21 |
| 24 | 0 |
| 25 | 35 |
| 26 | 0 |
| 27 | -21 |
| 28 | 0 |
| 29 | 8 |
| 30 | -28 |
| 31 | 0 |
| 32 | 70 |
| 33 | 0 |
| 34 | -84 |
| 35 | 0 |
| 36 | 17 |
| 37 | 9 |
| 38 | -36 |
| 39 | 0 |
| 40 | 126 |
| 41 | 0 |
| 42 | -252 |
| 43 | 0 |
| 44 | 153 |
| 45 | 0 |
| 46 | 10 |
| 47 | -45 |
| 48 | 0 |
| 49 | 210 |
| 50 | 0 |
| 51 | -630 |
| 52 | 0 |
| 53 | 765 |
| 54 | 0 |
| 55 | -155 |
| 56 | 11 |
| 57 | -55 |
| 58 | 0 |
| 59 | 330 |
| 60 | 0 |
| 61 | -1386 |
| 62 | 0 |
| 63 | 2805 |
| 64 | 0 |
| 65 | -1705 |
| 66 | 0 |
| 67 | 12 |
| 68 | -66 |
| 69 | 0 |
| 70 | 495 |
[1,2,-1,3,-3,0,4,-6,0,1,5,-10,0,5,0,6,-15,0,15,0, -3,7,-21,0,35,0,-21,0,8,-28,0,70,0,-84,0,17,9,-36, 0,126,0,-252,0,153,0,10,-45,0,210,0,-630,0,765,0, -155,11,-55,0,330,0,-1386,0,2805,0,-1705,0,12,-66, 0,495] |