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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 0 |
| 3 | 7385 |
| 4 | 28315 |
| 5 | 427987 |
| 6 | 1398635 |
| 7 | 10063590 |
| 8 | 30106965 |
| 9 | 148903370 |
| 10 | 415546516 |
| 11 | 1630361950 |
| 12 | 4294071285 |
| 13 | 14375319490 |
| 14 | 36019030960 |
| 15 | 107362236457 |
| 16 | 257518347380 |
| 17 | 702230132030 |
| 18 | 1620548828150 |
| 19 | 4117804435185 |
| 20 | 9180947306314 |
| 21 | 22023446814405 |
| 22 | 47606945661555 |
[1,0,0,7385,28315,427987,1398635,10063590, 30106965,148903370,415546516,1630361950, 4294071285,14375319490,36019030960,107362236457, 257518347380,702230132030,1620548828150, 4117804435185,9180947306314,22023446814405, 47606945661555] |