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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 4 |
| 3 | 6 |
| 4 | 10 |
| 5 | 19 |
| 6 | 33 |
| 7 | 58 |
| 8 | 110 |
| 9 | 205 |
| 10 | 379 |
| 11 | 723 |
| 12 | 1383 |
| 13 | 2630 |
| 14 | 5056 |
| 15 | 9770 |
| 16 | 18846 |
| 17 | 36485 |
| 18 | 70891 |
| 19 | 137785 |
| 20 | 268197 |
| 21 | 523176 |
| 22 | 1021490 |
| 23 | 1996255 |
| 24 | 3906299 |
| 25 | 7650804 |
| 26 | 14995686 |
| 27 | 29417270 |
| 28 | 57751714 |
| 29 | 113448331 |
| 30 | 223002449 |
| 31 | 438614490 |
| 32 | 863149766 |
| 33 | 1699458781 |
[1,2,4,6,10,19,33,58,110,205,379,723,1383,2630, 5056,9770,18846,36485,70891,137785,268197,523176, 1021490,1996255,3906299,7650804,14995686,29417270, 57751714,113448331,223002449,438614490,863149766, 1699458781] |