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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 7 |
| 3 | 29 |
| 4 | 109 |
| 5 | 416 |
| 6 | 1596 |
| 7 | 6105 |
| 8 | 23362 |
| 9 | 89415 |
| 10 | 342193 |
| 11 | 1309593 |
| 12 | 5011920 |
| 13 | 19180976 |
| 14 | 73406985 |
| 15 | 280933906 |
| 16 | 1075154535 |
| 17 | 4114694797 |
| 18 | 15747237101 |
| 19 | 60265824784 |
| 20 | 230641706484 |
| 21 | 882682631025 |
| 22 | 3378090801226 |
| 23 | 12928199853783 |
| 24 | 49477163668857 |
| 25 | 189352713633433 |
[1,2,7,29,109,416,1596,6105,23362,89415,342193, 1309593,5011920,19180976,73406985,280933906, 1075154535,4114694797,15747237101,60265824784, 230641706484,882682631025,3378090801226, 12928199853783,49477163668857,189352713633433] |