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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 8 |
| 3 | 29 |
| 4 | 122 |
| 5 | 516 |
| 6 | 2275 |
| 7 | 10063 |
| 8 | 45677 |
| 9 | 208078 |
| 10 | 959078 |
| 11 | 4449565 |
| 12 | 20770805 |
| 13 | 97420555 |
| 14 | 459170757 |
| 15 | 2171832581 |
| 16 | 10307926187 |
| 17 | 49070391239 |
| 18 | 234218338080 |
| 19 | 1120565600586 |
| 20 | 5372827196955 |
| 21 | 25811427398839 |
| 22 | 124218131253080 |
| 23 | 598779633094643 |
| 24 | 2890670050736226 |
| 25 | 13974041594587039 |
| 26 | 67639306569008879 |
[1,2,8,29,122,516,2275,10063,45677,208078,959078, 4449565,20770805,97420555,459170757,2171832581, 10307926187,49070391239,234218338080, 1120565600586,5372827196955,25811427398839, 124218131253080,598779633094643,2890670050736226, 13974041594587039,67639306569008879] |