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| n | a(n) |
|---|---|
| 4 | 1 |
| 5 | 0 |
| 6 | 0 |
| 7 | 0 |
| 8 | 69 |
| 9 | 250 |
| 10 | 418 |
| 11 | 658 |
| 12 | 34649 |
| 13 | 266267 |
| 14 | 1369372 |
| 15 | 5082045 |
| 16 | 76637635 |
| 17 | 876858377 |
| 18 | 7147459470 |
| 19 | 47396097511 |
| 20 | 552146011437 |
| 21 | 7418289082402 |
| 22 | 82776784289657 |
| 23 | 769968963165506 |
| 24 | 9270154198456497 |
| 25 | 136873296441831662 |
| 26 | 1900983368776814542 |
| 27 | 22997984983317347728 |
[1,0,0,0,69,250,418,658,34649,266267,1369372, 5082045,76637635,876858377,7147459470,47396097511, 552146011437,7418289082402,82776784289657, 769968963165506,9270154198456497, 136873296441831662,1900983368776814542, 22997984983317347728] |