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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 5 |
| 2 | 16 |
| 3 | 53 |
| 4 | 175 |
| 5 | 578 |
| 6 | 1909 |
| 7 | 6305 |
| 8 | 20824 |
| 9 | 68777 |
| 10 | 227155 |
| 11 | 750242 |
| 12 | 2477881 |
| 13 | 8183885 |
| 14 | 27029536 |
| 15 | 89272493 |
| 16 | 294847015 |
| 17 | 973813538 |
| 18 | 3216287629 |
| 19 | 10622676425 |
| 20 | 35084316904 |
| 21 | 115875627137 |
| 22 | 382711198315 |
| 23 | 1264009222082 |
| 24 | 4174738864561 |
| 25 | 13788225815765 |
| 26 | 45539416311856 |
[1,5,16,53,175,578,1909,6305,20824,68777,227155, 750242,2477881,8183885,27029536,89272493, 294847015,973813538,3216287629,10622676425, 35084316904,115875627137,382711198315, 1264009222082,4174738864561,13788225815765, 45539416311856] |