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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 1 |
| 3 | 3 |
| 4 | 7 |
| 5 | 14 |
| 6 | 16 |
| 7 | -77 |
| 8 | -922 |
| 9 | -6660 |
| 10 | -41264 |
| 11 | -233828 |
| 12 | -1218392 |
| 13 | -5607225 |
| 14 | -19220589 |
| 15 | 4397930 |
| 16 | 1016675382 |
| 17 | 14251497833 |
| 18 | 151695504253 |
| 19 | 1432992328055 |
| 20 | 12527186450276 |
| 21 | 102042171190168 |
| 22 | 760272520469199 |
| 23 | 4849866087637364 |
[0,0,1,3,7,14,16,-77,-922,-6660,-41264,-233828, -1218392,-5607225,-19220589,4397930,1016675382, 14251497833,151695504253,1432992328055, 12527186450276,102042171190168,760272520469199, 4849866087637364] |