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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 0 |
| 4 | 3 |
| 5 | 3 |
| 6 | -2 |
| 7 | 3 |
| 8 | 15 |
| 9 | 12 |
| 10 | -5 |
| 11 | -5 |
| 12 | 30 |
| 13 | 84 |
| 14 | 55 |
| 15 | -9 |
| 16 | -27 |
| 17 | 0 |
| 18 | 252 |
| 19 | 495 |
| 20 | 273 |
| 21 | -14 |
| 22 | -63 |
| 23 | -180 |
| 24 | 252 |
| 25 | 1980 |
| 26 | 3003 |
| 27 | 1428 |
| 28 | -20 |
| 29 | -99 |
| 30 | -612 |
| 31 | -1008 |
| 32 | 3630 |
| 33 | 15015 |
| 34 | 18564 |
| 35 | 7752 |
| 36 | -27 |
| 37 | -99 |
| 38 | -1200 |
| 39 | -5544 |
| 40 | -3465 |
| 41 | 39039 |
| 42 | 111384 |
| 43 | 116280 |
| 44 | 43263 |
| 45 | -35 |
| 46 | 0 |
| 47 | -1320 |
| 48 | -14280 |
| 49 | -45045 |
| 50 | 15015 |
| 51 | 371280 |
| 52 | 813960 |
| 53 | 735471 |
| 54 | 246675 |
| 55 | -44 |
| 56 | 286 |
| 57 | 510 |
[1,1,1,0,3,3,-2,3,15,12,-5,-5,30,84,55,-9,-27,0, 252,495,273,-14,-63,-180,252,1980,3003,1428,-20, -99,-612,-1008,3630,15015,18564,7752,-27,-99, -1200,-5544,-3465,39039,111384,116280,43263,-35,0, -1320,-14280,-45045,15015,371280,813960,735471, 246675,-44,286,510] |