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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | -12 |
| 4 | 180 |
| 5 | -4080 |
| 6 | 113400 |
| 7 | -3281040 |
| 8 | 75675600 |
| 9 | -207930240 |
| 10 | -54890589600 |
| 11 | -1623047025600 |
| 12 | -1372180725115200 |
| 13 | 354312481665542400 |
| 14 | 98331129549161308800 |
| 15 | -22733950460442373152000 |
| 16 | -23918355671347608543072000 |
| 17 | 1666438721774386195603968000 |
[1,2,-12,180,-4080,113400,-3281040,75675600, -207930240,-54890589600,-1623047025600, -1372180725115200,354312481665542400, 98331129549161308800,-22733950460442373152000, -23918355671347608543072000, 1666438721774386195603968000] |