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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 8 |
| 5 | 15 |
| 6 | 44 |
| 7 | 101 |
| 8 | 334 |
| 9 | 817 |
| 10 | 2752 |
| 11 | 7084 |
| 12 | 24607 |
| 13 | 67680 |
| 14 | 245864 |
| 15 | 697772 |
| 16 | 2553885 |
| 17 | 7409054 |
| 18 | 27480303 |
| 19 | 82521955 |
| 20 | 313794525 |
| 21 | 959852546 |
| 22 | 3664001178 |
| 23 | 11345504079 |
| 24 | 43619693769 |
| 25 | 138028015239 |
| 26 | 539448885144 |
| 27 | 1727930112762 |
| 28 | 6767820538432 |
| 29 | 21845264940373 |
| 30 | 85933511671898 |
| 31 | 281615411418059 |
| 32 | 1121090889944370 |
[1,1,2,3,8,15,44,101,334,817,2752,7084,24607, 67680,245864,697772,2553885,7409054,27480303, 82521955,313794525,959852546,3664001178, 11345504079,43619693769,138028015239,539448885144, 1727930112762,6767820538432,21845264940373, 85933511671898,281615411418059,1121090889944370] |