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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | -1 |
| 3 | 0 |
| 4 | -2 |
| 5 | 2 |
| 6 | 0 |
| 7 | -7 |
| 8 | 14 |
| 9 | -7 |
| 10 | 0 |
| 11 | -37 |
| 12 | 111 |
| 13 | -111 |
| 14 | 37 |
| 15 | 0 |
| 16 | -268 |
| 17 | 1072 |
| 18 | -1608 |
| 19 | 1072 |
| 20 | -268 |
| 21 | 0 |
| 22 | -2496 |
| 23 | 12480 |
| 24 | -24960 |
| 25 | 24960 |
| 26 | -12480 |
| 27 | 2496 |
| 28 | 0 |
| 29 | -28612 |
| 30 | 171672 |
| 31 | -429180 |
| 32 | 572240 |
| 33 | -429180 |
| 34 | 171672 |
| 35 | -28612 |
| 36 | 0 |
| 37 | -391189 |
| 38 | 2738323 |
| 39 | -8214969 |
| 40 | 13691615 |
| 41 | -13691615 |
| 42 | 8214969 |
| 43 | -2738323 |
| 44 | 391189 |
| 45 | 0 |
| 46 | -6230646 |
| 47 | 49845168 |
| 48 | -174458088 |
| 49 | 348916176 |
| 50 | -436145220 |
| 51 | 348916176 |
| 52 | -174458088 |
| 53 | 49845168 |
| 54 | -6230646 |
| 55 | 0 |
[1,0,-1,0,-2,2,0,-7,14,-7,0,-37,111,-111,37,0, -268,1072,-1608,1072,-268,0,-2496,12480,-24960, 24960,-12480,2496,0,-28612,171672,-429180,572240, -429180,171672,-28612,0,-391189,2738323,-8214969, 13691615,-13691615,8214969,-2738323,391189,0, -6230646,49845168,-174458088,348916176,-436145220, 348916176,-174458088,49845168,-6230646,0] |