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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 8 |
| 4 | 18 |
| 5 | 38 |
| 6 | 78 |
| 7 | 159 |
| 8 | 321 |
| 9 | 646 |
| 10 | 1297 |
| 11 | 2600 |
| 12 | 5207 |
| 13 | 10422 |
| 14 | 20852 |
| 15 | 41712 |
| 16 | 83433 |
| 17 | 166876 |
| 18 | 333762 |
| 19 | 667534 |
| 20 | 1335078 |
| 21 | 2670166 |
| 22 | 5340342 |
| 23 | 10680695 |
| 24 | 21361402 |
| 25 | 42722816 |
| 26 | 85445645 |
| 27 | 170891304 |
| 28 | 341782622 |
| 29 | 683565259 |
| 30 | 1367130534 |
| 31 | 2734261085 |
| 32 | 5468522187 |
| 33 | 10937044391 |
[1,3,8,18,38,78,159,321,646,1297,2600,5207,10422, 20852,41712,83433,166876,333762,667534,1335078, 2670166,5340342,10680695,21361402,42722816, 85445645,170891304,341782622,683565259,1367130534, 2734261085,5468522187,10937044391] |