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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | -5 |
| 3 | 78 |
| 4 | -1200 |
| 5 | 19680 |
| 6 | -351360 |
| 7 | 6854400 |
| 8 | -145797120 |
| 9 | 3367526400 |
| 10 | -84072038400 |
| 11 | 2258332876800 |
| 12 | -64990937088000 |
| 13 | 1995834890649600 |
| 14 | -65167516237824000 |
| 15 | 2254974602969088000 |
| 16 | -82443156980760576000 |
| 17 | 3176032637949050880000 |
| 18 | -128603097714237898752000 |
| 19 | 5460911310769351557120000 |
[1,-5,78,-1200,19680,-351360,6854400,-145797120, 3367526400,-84072038400,2258332876800, -64990937088000,1995834890649600, -65167516237824000,2254974602969088000, -82443156980760576000,3176032637949050880000, -128603097714237898752000, 5460911310769351557120000] |