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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 6 |
| 5 | 9 |
| 6 | 18 |
| 7 | 36 |
| 8 | 61 |
| 9 | 106 |
| 10 | 212 |
| 11 | 424 |
| 12 | 776 |
| 13 | 1449 |
| 14 | 2898 |
| 15 | 5796 |
| 16 | 11096 |
| 17 | 21486 |
| 18 | 42972 |
| 19 | 85944 |
| 20 | 168421 |
| 21 | 331914 |
| 22 | 663828 |
| 23 | 1327656 |
| 24 | 2630981 |
| 25 | 5227391 |
| 26 | 10454782 |
| 27 | 20909564 |
| 28 | 41648191 |
| 29 | 83053529 |
| 30 | 166107058 |
| 31 | 332214116 |
| 32 | 663226966 |
| 33 | 1324747321 |
| 34 | 2649494642 |
[1,2,4,6,9,18,36,61,106,212,424,776,1449,2898, 5796,11096,21486,42972,85944,168421,331914,663828, 1327656,2630981,5227391,10454782,20909564, 41648191,83053529,166107058,332214116,663226966, 1324747321,2649494642] |