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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 4 |
| 5 | 5 |
| 6 | 6 |
| 7 | 9 |
| 8 | 10 |
| 9 | 15 |
| 10 | 20 |
| 11 | 29 |
| 12 | 52 |
| 13 | 87 |
| 14 | 166 |
| 15 | 311 |
| 16 | 538 |
| 17 | 943 |
| 18 | 1682 |
| 19 | 2915 |
| 20 | 5054 |
| 21 | 8905 |
| 22 | 15904 |
| 23 | 28533 |
| 24 | 51826 |
| 25 | 95191 |
| 26 | 175402 |
| 27 | 325777 |
| 28 | 607542 |
| 29 | 1134191 |
| 30 | 2128922 |
| 31 | 3986433 |
| 32 | 7485522 |
| 33 | 14065135 |
| 34 | 26446388 |
| 35 | 49796025 |
| 36 | 93920770 |
| 37 | 177470237 |
| 38 | 335780796 |
| 39 | 636883269 |
| 40 | 1209603646 |
[1,2,3,4,5,6,9,10,15,20,29,52,87,166,311,538,943, 1682,2915,5054,8905,15904,28533,51826,95191, 175402,325777,607542,1134191,2128922,3986433, 7485522,14065135,26446388,49796025,93920770, 177470237,335780796,636883269,1209603646] |