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| n | a(n) |
|---|---|
| 0 | 3 |
| 1 | 5 |
| 2 | 9 |
| 3 | 18 |
| 4 | 36 |
| 5 | 72 |
| 6 | 144 |
| 7 | 287 |
| 8 | 573 |
| 9 | 1145 |
| 10 | 2290 |
| 11 | 4580 |
| 12 | 9159 |
| 13 | 18318 |
| 14 | 36636 |
| 15 | 73272 |
| 16 | 146543 |
| 17 | 293086 |
| 18 | 586172 |
| 19 | 1172344 |
| 20 | 2344688 |
| 21 | 4689375 |
| 22 | 9378749 |
| 23 | 18757498 |
| 24 | 37514996 |
| 25 | 75029991 |
| 26 | 150059982 |
| 27 | 300119964 |
| 28 | 600239928 |
| 29 | 1200479855 |
| 30 | 2400959709 |
| 31 | 4801919418 |
| 32 | 9603838835 |
[3,5,9,18,36,72,144,287,573,1145,2290,4580,9159, 18318,36636,73272,146543,293086,586172,1172344, 2344688,4689375,9378749,18757498,37514996, 75029991,150059982,300119964,600239928,1200479855, 2400959709,4801919418,9603838835] |