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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | -1 |
| 4 | 12 |
| 5 | -8 |
| 6 | 1 |
| 7 | 144 |
| 8 | -108 |
| 9 | 20 |
| 10 | -1 |
| 11 | 3600 |
| 12 | -2844 |
| 13 | 608 |
| 14 | -45 |
| 15 | 1 |
| 16 | 172800 |
| 17 | -140112 |
| 18 | 32028 |
| 19 | -2768 |
| 20 | 93 |
| 21 | -1 |
| 22 | 15724800 |
| 23 | -12922992 |
| 24 | 3054660 |
| 25 | -283916 |
| 26 | 11231 |
| 27 | -184 |
| 28 | 1 |
| 29 | 2641766400 |
| 30 | -2186787456 |
| 31 | 526105872 |
| 32 | -50752548 |
| 33 | 2170724 |
| 34 | -42143 |
| 35 | 352 |
| 36 | -1 |
| 37 | 808380518400 |
| 38 | -671798727936 |
| 39 | 163175184288 |
| 40 | -16056385560 |
[1,2,-1,12,-8,1,144,-108,20,-1,3600,-2844,608,-45, 1,172800,-140112,32028,-2768,93,-1,15724800, -12922992,3054660,-283916,11231,-184,1,2641766400, -2186787456,526105872,-50752548,2170724,-42143, 352,-1,808380518400,-671798727936,163175184288, -16056385560] |