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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | -2 |
| 2 | -16 |
| 3 | -88 |
| 4 | -384 |
| 5 | -1312 |
| 6 | -2816 |
| 7 | 3712 |
| 8 | 86016 |
| 9 | 613888 |
| 10 | 3190784 |
| 11 | 13248512 |
| 12 | 42172416 |
| 13 | 72409088 |
| 14 | -264175616 |
| 15 | -3561586688 |
| 16 | -23209181184 |
| 17 | -114441715712 |
| 18 | -451350102016 |
| 19 | -1321966501888 |
| 20 | -1548729974784 |
| 21 | 14049490239488 |
| 22 | 143370521411584 |
| 23 | 865974366502912 |
| 24 | 4060384503791616 |
| 25 | 15163588700274688 |
[0,-2,-16,-88,-384,-1312,-2816,3712,86016,613888, 3190784,13248512,42172416,72409088,-264175616, -3561586688,-23209181184,-114441715712, -451350102016,-1321966501888,-1548729974784, 14049490239488,143370521411584,865974366502912, 4060384503791616,15163588700274688] |