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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 0 |
| 3 | -2 |
| 4 | 0 |
| 5 | 2 |
| 6 | 12 |
| 7 | 0 |
| 8 | -2 |
| 9 | -16 |
| 10 | -80 |
| 11 | 0 |
| 12 | 2 |
| 13 | 20 |
| 14 | 120 |
| 15 | 560 |
| 16 | 0 |
| 17 | -2 |
| 18 | -24 |
| 19 | -168 |
| 20 | -896 |
| 21 | -4032 |
| 22 | 0 |
| 23 | 2 |
| 24 | 28 |
| 25 | 224 |
| 26 | 1344 |
| 27 | 6720 |
| 28 | 29568 |
| 29 | 0 |
| 30 | -2 |
| 31 | -32 |
| 32 | -288 |
| 33 | -1920 |
| 34 | -10560 |
| 35 | -50688 |
| 36 | -219648 |
| 37 | 0 |
| 38 | 2 |
| 39 | 36 |
| 40 | 360 |
| 41 | 2640 |
| 42 | 15840 |
| 43 | 82368 |
| 44 | 384384 |
| 45 | 1647360 |
| 46 | 0 |
| 47 | -2 |
| 48 | -40 |
| 49 | -440 |
| 50 | -3520 |
| 51 | -22880 |
| 52 | -128128 |
| 53 | -640640 |
| 54 | -2928640 |
| 55 | -12446720 |
[1,0,-2,0,2,12,0,-2,-16,-80,0,2,20,120,560,0,-2, -24,-168,-896,-4032,0,2,28,224,1344,6720,29568,0, -2,-32,-288,-1920,-10560,-50688,-219648,0,2,36, 360,2640,15840,82368,384384,1647360,0,-2,-40,-440, -3520,-22880,-128128,-640640,-2928640,-12446720] |