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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 4 |
| 3 | 8 |
| 4 | 17 |
| 5 | 39 |
| 6 | 95 |
| 7 | 241 |
| 8 | 629 |
| 9 | 1676 |
| 10 | 4533 |
| 11 | 12392 |
| 12 | 34145 |
| 13 | 94670 |
| 14 | 263853 |
| 15 | 738744 |
| 16 | 2076817 |
| 17 | 5860033 |
| 18 | 16589996 |
| 19 | 47108718 |
| 20 | 134136047 |
| 21 | 382889797 |
| 22 | 1095452434 |
| 23 | 3140672834 |
| 24 | 9021699845 |
| 25 | 25961239919 |
| 26 | 74829970930 |
| 27 | 216016298741 |
| 28 | 624469525203 |
[1,2,4,8,17,39,95,241,629,1676,4533,12392,34145, 94670,263853,738744,2076817,5860033,16589996, 47108718,134136047,382889797,1095452434, 3140672834,9021699845,25961239919,74829970930, 216016298741,624469525203] |