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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | -1 |
| 3 | -2 |
| 4 | 5 |
| 5 | -8 |
| 6 | -16 |
| 7 | -32 |
| 8 | -48 |
| 9 | -64 |
| 10 | -80 |
| 11 | 224 |
| 12 | -368 |
| 13 | 312 |
| 14 | -205 |
| 15 | -2850 |
| 16 | 5905 |
| 17 | 1817592 |
| 18 | -4329936 |
| 19 | -2004480 |
| 20 | -442800 |
| 21 | 20967000 |
| 22 | -349316425 |
| 23 | 1853293420 |
| 24 | -6937330896 |
| 25 | 24280673168 |
| 26 | -18727955840 |
| 27 | -31062538500 |
| 28 | -42332130415 |
| 29 | 2736294281648 |
| 30 | -27940194392976 |
[1,0,-1,-2,5,-8,-16,-32,-48,-64,-80,224,-368,312, -205,-2850,5905,1817592,-4329936,-2004480,-442800, 20967000,-349316425,1853293420,-6937330896, 24280673168,-18727955840,-31062538500, -42332130415,2736294281648,-27940194392976] |