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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 22 |
| 3 | 269 |
| 4 | 5624 |
| 5 | 64346 |
| 6 | 1435644 |
| 7 | 17231678 |
| 8 | 394101698 |
| 9 | 4795863215 |
| 10 | 111385873044 |
| 11 | 1367910381793 |
| 12 | 32104125661092 |
| 13 | 396732928643199 |
| 14 | 9380176155748724 |
| 15 | 116431632349956000 |
| 16 | 2768141124993190440 |
| 17 | 34474283501877795558 |
[0,22,269,5624,64346,1435644,17231678,394101698, 4795863215,111385873044,1367910381793, 32104125661092,396732928643199,9380176155748724, 116431632349956000,2768141124993190440, 34474283501877795558] |