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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | -3 |
| 3 | 20 |
| 4 | -245 |
| 5 | 4290 |
| 6 | -114422 |
| 7 | 4086800 |
| 8 | -203647509 |
| 9 | 12920587070 |
| 10 | -1053926397590 |
| 11 | 105178069321944 |
| 12 | -12765014959365682 |
| 13 | 1838898931467398164 |
| 14 | -311221726754896488780 |
| 15 | 61047560951879121055296 |
| 16 | -13747598006865584455353165 |
| 17 | 3521759025274977423306328182 |
| 18 | -1018406456608128511401443183654 |
[1,1,-3,20,-245,4290,-114422,4086800,-203647509, 12920587070,-1053926397590,105178069321944, -12765014959365682,1838898931467398164, -311221726754896488780,61047560951879121055296, -13747598006865584455353165, 3521759025274977423306328182, -1018406456608128511401443183654] |