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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | -1 |
| 2 | 1 |
| 3 | 0 |
| 4 | -1 |
| 5 | 120 |
| 6 | 1 |
| 7 | -672 |
| 8 | 0 |
| 9 | -1 |
| 10 | 2160 |
| 11 | -120960 |
| 12 | 1 |
| 13 | -5280 |
| 14 | 1584000 |
| 15 | 0 |
| 16 | -1 |
| 17 | 10920 |
| 18 | -10250240 |
| 19 | 482786304 |
| 20 | 1 |
| 21 | -20160 |
| 22 | 45427200 |
| 23 | -11480268800 |
| 24 | 0 |
| 25 | -1 |
| 26 | 34272 |
| 27 | -157651200 |
| 28 | 124816613376 |
| 29 | -5405660282880 |
| 30 | 1 |
| 31 | -54720 |
| 32 | 460158720 |
| 33 | -875447623680 |
| 34 | 203526629130240 |
| 35 | 0 |
[1,-1,1,0,-1,120,1,-672,0,-1,2160,-120960,1,-5280, 1584000,0,-1,10920,-10250240,482786304,1,-20160, 45427200,-11480268800,0,-1,34272,-157651200, 124816613376,-5405660282880,1,-54720,460158720, -875447623680,203526629130240,0] |