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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | -12 |
| 2 | 228 |
| 3 | -3504 |
| 4 | 44580 |
| 5 | -298032 |
| 6 | 1407504 |
| 7 | -275772096 |
| 8 | 21324125988 |
| 9 | -966349948080 |
| 10 | 32198201397648 |
| 11 | -831808446595776 |
| 12 | 16275197594916624 |
| 13 | -210881419152530112 |
| 14 | 1110165241205298240 |
| 15 | -28746364298042321664 |
| 16 | 4877709692143697517348 |
| 17 | -323151109677783574203312 |
| 18 | 13976671241536620108719376 |
[1,-12,228,-3504,44580,-298032,1407504,-275772096, 21324125988,-966349948080,32198201397648, -831808446595776,16275197594916624, -210881419152530112,1110165241205298240, -28746364298042321664,4877709692143697517348, -323151109677783574203312, 13976671241536620108719376] |