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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 0 |
| 3 | -15 |
| 4 | 5 |
| 5 | 18 |
| 6 | 66 |
| 7 | 298 |
| 8 | 1511 |
| 9 | 8670 |
| 10 | 55168 |
| 11 | 386394 |
| 12 | 2951673 |
| 13 | 24428654 |
| 14 | 217723390 |
| 15 | 2079109386 |
| 16 | 21177620171 |
| 17 | 229195610430 |
| 18 | 2626388037372 |
| 19 | 31768201320634 |
| 20 | 404485298533085 |
| 21 | 5407570127090958 |
| 22 | 75736453324821754 |
| 23 | 1108952444876609898 |
| 24 | 16943545270848408495 |
[0,0,0,-15,5,18,66,298,1511,8670,55168,386394, 2951673,24428654,217723390,2079109386,21177620171, 229195610430,2626388037372,31768201320634, 404485298533085,5407570127090958, 75736453324821754,1108952444876609898, 16943545270848408495] |