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| n | a(n) |
|---|---|
| 0 | 63 |
| 1 | 17 |
| 2 | 5 |
| 3 | 1 |
| 4 | 4 |
| 5 | 18 |
| 6 | 96 |
| 7 | 510 |
| 8 | 2580 |
| 9 | 12522 |
| 10 | 58920 |
| 11 | 270870 |
| 12 | 1223292 |
[63,17,5,1,4,18,96,510,2580,12522,58920,270870, 1223292] |