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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 4 |
| 3 | 8 |
| 4 | 15 |
| 5 | 30 |
| 6 | 57 |
| 7 | 112 |
| 8 | 216 |
| 9 | 420 |
| 10 | 815 |
| 11 | 1580 |
| 12 | 3069 |
| 13 | 5950 |
| 14 | 11552 |
| 15 | 22408 |
| 16 | 43487 |
| 17 | 84378 |
| 18 | 163725 |
| 19 | 317700 |
| 20 | 616444 |
| 21 | 1196172 |
| 22 | 2321007 |
| 23 | 4503704 |
| 24 | 8738921 |
| 25 | 16956954 |
| 26 | 32903164 |
| 27 | 63845000 |
| 28 | 123884479 |
| 29 | 240384374 |
| 30 | 466440273 |
| 31 | 905077080 |
| 32 | 1756205088 |
[1,2,4,8,15,30,57,112,216,420,815,1580,3069,5950, 11552,22408,43487,84378,163725,317700,616444, 1196172,2321007,4503704,8738921,16956954,32903164, 63845000,123884479,240384374,466440273,905077080, 1756205088] |