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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 2 |
| 3 | 2 |
| 4 | 3 |
| 5 | 0 |
| 6 | 13 |
| 7 | -50 |
| 8 | 289 |
| 9 | -1693 |
| 10 | 10736 |
| 11 | -72091 |
| 12 | 510498 |
| 13 | -3792518 |
| 14 | 29447687 |
| 15 | -238250274 |
| 16 | 2003475307 |
| 17 | -17473865437 |
| 18 | 157785848332 |
| 19 | -1472797717102 |
| 20 | 14191079794761 |
| 21 | -140977192451948 |
| 22 | 1442305028220567 |
| 23 | -15180799919267781 |
| 24 | 164228909550516306 |
| 25 | -1824477798876645279 |
[0,1,2,2,3,0,13,-50,289,-1693,10736,-72091,510498, -3792518,29447687,-238250274,2003475307, -17473865437,157785848332,-1472797717102, 14191079794761,-140977192451948,1442305028220567, -15180799919267781,164228909550516306, -1824477798876645279] |