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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 4 |
| 3 | 6 |
| 4 | 11 |
| 5 | 18 |
| 6 | 32 |
| 7 | 54 |
| 8 | 95 |
| 9 | 164 |
| 10 | 291 |
| 11 | 514 |
| 12 | 923 |
| 13 | 1656 |
| 14 | 3000 |
| 15 | 5442 |
| 16 | 9942 |
| 17 | 18216 |
| 18 | 33564 |
| 19 | 62040 |
| 20 | 115167 |
| 21 | 214404 |
| 22 | 400497 |
| 23 | 750070 |
| 24 | 1408734 |
| 25 | 2652088 |
| 26 | 5004833 |
| 27 | 9464616 |
| 28 | 17935137 |
| 29 | 34049044 |
| 30 | 64754844 |
| 31 | 123351410 |
| 32 | 235335966 |
| 33 | 449632300 |
| 34 | 860241606 |
| 35 | 1647932000 |
[1,2,4,6,11,18,32,54,95,164,291,514,923,1656,3000, 5442,9942,18216,33564,62040,115167,214404,400497, 750070,1408734,2652088,5004833,9464616,17935137, 34049044,64754844,123351410,235335966,449632300, 860241606,1647932000] |