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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 9 |
| 3 | 24 |
| 4 | 67 |
| 5 | 244 |
| 6 | 1280 |
| 7 | 5637 |
| 8 | 32909 |
| 9 | 212185 |
| 10 | 1609756 |
| 11 | 13476199 |
| 12 | 134461394 |
[1,9,24,67,244,1280,5637,32909,212185,1609756, 13476199,134461394] |