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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 17 |
| 4 | 75 |
| 5 | 295 |
| 6 | 1349 |
| 7 | 5729 |
| 8 | 26757 |
| 9 | 118527 |
| 10 | 560259 |
| 11 | 2546099 |
| 12 | 12144117 |
| 13 | 56151281 |
| 14 | 269644087 |
| 15 | 1262417629 |
| 16 | 6093239571 |
| 17 | 28796251075 |
| 18 | 139545443435 |
| 19 | 664306612693 |
| 20 | 3229548391107 |
| 21 | 15463843514919 |
| 22 | 75375535979473 |
| 23 | 362624920462911 |
| 24 | 1771412430257817 |
| 25 | 8555451112575391 |
| 26 | 41870416595861169 |
| 27 | 202886096194456097 |
[1,1,5,17,75,295,1349,5729,26757,118527,560259, 2546099,12144117,56151281,269644087,1262417629, 6093239571,28796251075,139545443435,664306612693, 3229548391107,15463843514919,75375535979473, 362624920462911,1771412430257817,8555451112575391, 41870416595861169,202886096194456097] |