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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 2 |
| 5 | 3 |
| 6 | 5 |
| 7 | 9 |
| 8 | 18 |
| 9 | 35 |
| 10 | 73 |
| 11 | 151 |
| 12 | 324 |
| 13 | 691 |
| 14 | 1503 |
| 15 | 3277 |
| 16 | 7212 |
| 17 | 15927 |
| 18 | 35407 |
| 19 | 78967 |
| 20 | 176942 |
| 21 | 397717 |
| 22 | 897079 |
| 23 | 2029071 |
| 24 | 4602438 |
| 25 | 10464647 |
| 26 | 23849545 |
| 27 | 54468627 |
| 28 | 124646180 |
| 29 | 285762575 |
| 30 | 656268311 |
| 31 | 1509570433 |
| 32 | 3477615648 |
| 33 | 8022765075 |
[1,1,1,2,3,5,9,18,35,73,151,324,691,1503,3277, 7212,15927,35407,78967,176942,397717,897079, 2029071,4602438,10464647,23849545,54468627, 124646180,285762575,656268311,1509570433, 3477615648,8022765075] |