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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 12 |
| 3 | 49 |
| 4 | 213 |
| 5 | 949 |
| 6 | 4315 |
| 7 | 19948 |
| 8 | 93051 |
| 9 | 438391 |
| 10 | 2076618 |
| 11 | 9895800 |
| 12 | 47347875 |
| 13 | 227405295 |
| 14 | 1095653934 |
| 15 | 5292729849 |
| 16 | 25629887924 |
| 17 | 124354876370 |
| 18 | 604493596562 |
| 19 | 2943061130320 |
| 20 | 14349482523619 |
| 21 | 70053868908239 |
| 22 | 342395885103390 |
| 23 | 1675286128579784 |
| 24 | 8204662187789668 |
| 25 | 40217855422498911 |
| 26 | 197298725918886144 |
[1,3,12,49,213,949,4315,19948,93051,438391, 2076618,9895800,47347875,227405295,1095653934, 5292729849,25629887924,124354876370,604493596562, 2943061130320,14349482523619,70053868908239, 342395885103390,1675286128579784,8204662187789668, 40217855422498911,197298725918886144] |