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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 0 |
| 3 | 2 |
| 4 | 0 |
| 5 | 2 |
| 6 | 1 |
| 7 | 6 |
| 8 | -2 |
| 9 | 11 |
| 10 | -1 |
| 11 | 30 |
| 12 | -21 |
| 13 | 76 |
| 14 | -60 |
| 15 | 223 |
| 16 | -245 |
| 17 | 653 |
| 18 | -817 |
| 19 | 2031 |
| 20 | -2935 |
| 21 | 6521 |
| 22 | -10067 |
| 23 | 21455 |
| 24 | -35425 |
| 25 | 72152 |
| 26 | -123756 |
| 27 | 246752 |
| 28 | -436854 |
| 29 | 855852 |
| 30 | -1546777 |
| 31 | 3001811 |
| 32 | -5513604 |
| 33 | 10630676 |
| 34 | -19747742 |
| 35 | 37949424 |
| 36 | -71115077 |
| 37 | 136415279 |
| 38 | -257301742 |
| 39 | 493313335 |
[1,1,0,2,0,2,1,6,-2,11,-1,30,-21,76,-60,223,-245, 653,-817,2031,-2935,6521,-10067,21455,-35425, 72152,-123756,246752,-436854,855852,-1546777, 3001811,-5513604,10630676,-19747742,37949424, -71115077,136415279,-257301742,493313335] |