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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 1 |
| 5 | 45 |
| 6 | 1194 |
| 7 | 55777 |
| 8 | 4471175 |
| 9 | 669049507 |
| 10 | 187616301623 |
| 11 | 98793450008033 |
| 12 | 97702667035688951 |
[0,0,0,1,45,1194,55777,4471175,669049507, 187616301623,98793450008033,97702667035688951] |