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| n | a(n) |
|---|---|
| 1 | 5 |
| 2 | 21 |
| 3 | 30 |
| 4 | 93 |
| 5 | 249 |
| 6 | 544 |
| 7 | 1372 |
| 8 | 3411 |
| 9 | 8269 |
| 10 | 20472 |
| 11 | 50397 |
| 12 | 123803 |
| 13 | 305272 |
| 14 | 751590 |
| 15 | 1849735 |
| 16 | 4556239 |
| 17 | 11219928 |
| 18 | 27625541 |
| 19 | 68032151 |
| 20 | 167535478 |
| 21 | 412552316 |
| 22 | 1015939459 |
| 23 | 2501834023 |
| 24 | 6160893450 |
| 25 | 15171602577 |
| 26 | 37361209577 |
| 27 | 92004521524 |
[5,21,30,93,249,544,1372,3411,8269,20472,50397, 123803,305272,751590,1849735,4556239,11219928, 27625541,68032151,167535478,412552316,1015939459, 2501834023,6160893450,15171602577,37361209577, 92004521524] |