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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 4 |
| 3 | 8 |
| 4 | 14 |
| 5 | 24 |
| 6 | 42 |
| 7 | 75 |
| 8 | 138 |
| 9 | 261 |
| 10 | 500 |
| 11 | 960 |
| 12 | 1838 |
| 13 | 3505 |
| 14 | 6669 |
| 15 | 12698 |
| 16 | 24254 |
| 17 | 46533 |
| 18 | 89679 |
| 19 | 173472 |
| 20 | 336440 |
| 21 | 653616 |
| 22 | 1271244 |
| 23 | 2474786 |
| 24 | 4822414 |
| 25 | 9407279 |
| 26 | 18372967 |
| 27 | 35926706 |
| 28 | 70331337 |
| 29 | 137822864 |
| 30 | 270318832 |
| 31 | 530594784 |
| 32 | 1042182332 |
| 33 | 2048302421 |
[1,2,4,8,14,24,42,75,138,261,500,960,1838,3505, 6669,12698,24254,46533,89679,173472,336440,653616, 1271244,2474786,4822414,9407279,18372967,35926706, 70331337,137822864,270318832,530594784,1042182332, 2048302421] |