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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | -1 |
| 3 | 4 |
| 4 | -7 |
| 5 | 19 |
| 6 | -40 |
| 7 | 97 |
| 8 | -217 |
| 9 | 508 |
| 10 | -1159 |
| 11 | 2683 |
| 12 | -6160 |
| 13 | 14209 |
| 14 | -32689 |
| 15 | 75316 |
| 16 | -173383 |
| 17 | 399331 |
| 18 | -919480 |
| 19 | 2117473 |
| 20 | -4875913 |
| 21 | 11228332 |
| 22 | -25856071 |
| 23 | 59541067 |
| 24 | -137109280 |
| 25 | 315732481 |
| 26 | -727060321 |
| 27 | 1674257764 |
| 28 | -3855438727 |
| 29 | 8878212019 |
| 30 | -20444528200 |
| 31 | 47079164257 |
| 32 | -108412748857 |
[0,1,-1,4,-7,19,-40,97,-217,508,-1159,2683,-6160, 14209,-32689,75316,-173383,399331,-919480,2117473, -4875913,11228332,-25856071,59541067,-137109280, 315732481,-727060321,1674257764,-3855438727, 8878212019,-20444528200,47079164257,-108412748857] |