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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 7 |
| 5 | 13 |
| 6 | 24 |
| 7 | 42 |
| 8 | 77 |
| 9 | 138 |
| 10 | 249 |
| 11 | 454 |
| 12 | 823 |
| 13 | 1493 |
| 14 | 2719 |
| 15 | 4969 |
| 16 | 9060 |
| 17 | 16588 |
| 18 | 30375 |
| 19 | 55672 |
| 20 | 102330 |
| 21 | 188334 |
| 22 | 346624 |
| 23 | 639280 |
| 24 | 1179742 |
| 25 | 2178907 |
| 26 | 4029060 |
| 27 | 7456271 |
| 28 | 13806301 |
| 29 | 25587417 |
| 30 | 47452133 |
| 31 | 88057540 |
| 32 | 163518793 |
| 33 | 303826088 |
| 34 | 564825654 |
[1,2,4,7,13,24,42,77,138,249,454,823,1493,2719, 4969,9060,16588,30375,55672,102330,188334,346624, 639280,1179742,2178907,4029060,7456271,13806301, 25587417,47452133,88057540,163518793,303826088, 564825654] |