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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 5 |
| 3 | 12 |
| 4 | 28 |
| 5 | 67 |
| 6 | 156 |
| 7 | 370 |
| 8 | 866 |
| 9 | 2044 |
| 10 | 4799 |
| 11 | 11304 |
| 12 | 26574 |
| 13 | 62547 |
| 14 | 147108 |
| 15 | 346149 |
| 16 | 814270 |
| 17 | 1915795 |
| 18 | 4506952 |
| 19 | 10603417 |
| 20 | 24945414 |
| 21 | 58687660 |
| 22 | 138068915 |
| 23 | 324824928 |
| 24 | 764187814 |
| 25 | 1797846170 |
| 26 | 4229645000 |
| 27 | 9950753025 |
| 28 | 23410332344 |
| 29 | 55075627972 |
| 30 | 129572006209 |
[1,2,5,12,28,67,156,370,866,2044,4799,11304,26574, 62547,147108,346149,814270,1915795,4506952, 10603417,24945414,58687660,138068915,324824928, 764187814,1797846170,4229645000,9950753025, 23410332344,55075627972,129572006209] |