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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 0 |
| 3 | 8 |
| 4 | 0 |
| 5 | 1 |
| 6 | 82 |
| 7 | 0 |
| 8 | 0 |
| 9 | 43 |
| 10 | 868 |
| 11 | 0 |
| 12 | 0 |
| 13 | 11 |
| 14 | 920 |
| 15 | 9726 |
| 16 | 0 |
| 17 | 0 |
| 18 | 1 |
| 19 | 590 |
| 20 | 15524 |
| 21 | 113536 |
| 22 | 0 |
| 23 | 0 |
| 24 | 0 |
| 25 | 243 |
| 26 | 15904 |
| 27 | 243040 |
| 28 | 1366570 |
[1,0,8,0,1,82,0,0,43,868,0,0,11,920,9726,0,0,1, 590,15524,113536,0,0,0,243,15904,243040,1366570] |