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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 9 |
| 3 | 32 |
| 4 | 126 |
| 5 | 538 |
| 6 | 2429 |
| 7 | 11412 |
| 8 | 55201 |
| 9 | 272993 |
| 10 | 1373784 |
| 11 | 7011297 |
| 12 | 36201841 |
| 13 | 188761743 |
| 14 | 992491049 |
| 15 | 5256244537 |
| 16 | 28013213196 |
| 17 | 150128293038 |
| 18 | 808543940999 |
| 19 | 4373798584407 |
| 20 | 23753913152691 |
| 21 | 129469596050953 |
| 22 | 707969244301884 |
| 23 | 3882857013894482 |
| 24 | 21353585584100401 |
[1,3,9,32,126,538,2429,11412,55201,272993,1373784, 7011297,36201841,188761743,992491049,5256244537, 28013213196,150128293038,808543940999, 4373798584407,23753913152691,129469596050953, 707969244301884,3882857013894482, 21353585584100401] |