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| n | a(n) |
|---|---|
| 0 | 3 |
| 1 | 14 |
| 2 | 57 |
| 3 | 235 |
| 4 | 969 |
| 5 | 4014 |
| 6 | 16695 |
| 7 | 69678 |
| 8 | 291609 |
| 9 | 1223060 |
| 10 | 5138488 |
| 11 | 21617717 |
| 12 | 91044538 |
| 13 | 383775880 |
| 14 | 1618868769 |
| 15 | 6832842691 |
| 16 | 28853864329 |
| 17 | 121894728098 |
| 18 | 515129513163 |
| 19 | 2177588642423 |
| 20 | 9207559005080 |
| 21 | 38940990014941 |
| 22 | 164721537694077 |
| 23 | 696889444599910 |
[3,14,57,235,969,4014,16695,69678,291609,1223060, 5138488,21617717,91044538,383775880,1618868769, 6832842691,28853864329,121894728098,515129513163, 2177588642423,9207559005080,38940990014941, 164721537694077,696889444599910] |