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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 0 |
| 7 | 0 |
| 8 | 244 |
| 9 | 2841 |
| 10 | 17844 |
| 11 | 80289 |
| 12 | 290004 |
| 13 | 893607 |
| 14 | 2438436 |
| 15 | 6043911 |
| 16 | 13840224 |
| 17 | 29694274 |
| 18 | 60220488 |
| 19 | 116488506 |
| 20 | 215985456 |
[0,0,0,0,0,0,0,244,2841,17844,80289,290004,893607, 2438436,6043911,13840224,29694274,60220488, 116488506,215985456] |