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| n | a(n) |
|---|---|
| 2 | 11 |
| 3 | 281 |
| 4 | 2267 |
| 5 | 26881 |
| 6 | 464447 |
| 7 | 6462667 |
| 8 | 0 |
| 9 | 0 |
| 10 | 0 |
| 11 | 0 |
| 12 | 0 |
| 13 | 0 |
| 14 | 0 |
| 15 | 0 |
| 16 | 0 |
| 17 | 0 |
| 18 | 0 |
[11,281,2267,26881,464447,6462667,0,0,0,0,0,0,0,0, 0,0,0] |