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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 9 |
| 2 | 40 |
| 3 | 161 |
| 4 | 648 |
| 5 | 51841 |
| 6 | 207368 |
| 7 | 5374978561 |
| 8 | 21499914248 |
| 9 | 57780789062419261441 |
| 10 | 231123156249677045768 |
| 11 | 6677239169351578707225356193679818792961 |
| 12 | 26708956677406314828901424774719275171848 |
[1,9,40,161,648,51841,207368,5374978561, 21499914248,57780789062419261441, 231123156249677045768, 6677239169351578707225356193679818792961, 26708956677406314828901424774719275171848] |