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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 1 |
| 5 | -4 |
| 6 | 10 |
| 7 | -20 |
| 8 | 36 |
| 9 | -56 |
| 10 | 80 |
| 11 | -120 |
| 12 | 176 |
| 13 | -220 |
| 14 | 266 |
| 15 | -368 |
| 16 | 491 |
| 17 | -560 |
| 18 | 634 |
| 19 | -816 |
| 20 | 1050 |
| 21 | -1160 |
| 22 | 1210 |
| 23 | -1540 |
| 24 | 1982 |
| 25 | -2028 |
| 26 | 2080 |
| 27 | -2656 |
| 28 | 3192 |
| 29 | -3276 |
| 30 | 3380 |
| 31 | -4060 |
| 32 | 4986 |
| 33 | -5080 |
| 34 | 4896 |
| 35 | -6008 |
| 36 | 7345 |
| 37 | -7140 |
| 38 | 6954 |
| 39 | -8656 |
| 40 | 10224 |
| 41 | -9880 |
| 42 | 9796 |
| 43 | -11480 |
| 44 | 13552 |
| 45 | -13668 |
| 46 | 12650 |
[0,0,0,1,-4,10,-20,36,-56,80,-120,176,-220,266, -368,491,-560,634,-816,1050,-1160,1210,-1540,1982, -2028,2080,-2656,3192,-3276,3380,-4060,4986,-5080, 4896,-6008,7345,-7140,6954,-8656,10224,-9880,9796, -11480,13552,-13668,12650] |