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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 3 |
| 5 | 6 |
| 6 | 11 |
| 7 | 20 |
| 8 | 38 |
| 9 | 71 |
| 10 | 133 |
| 11 | 250 |
| 12 | 469 |
| 13 | 882 |
| 14 | 1657 |
| 15 | 3114 |
| 16 | 5852 |
| 17 | 10998 |
| 18 | 20669 |
| 19 | 38845 |
| 20 | 73004 |
| 21 | 137203 |
| 22 | 257857 |
| 23 | 484612 |
| 24 | 910773 |
| 25 | 1711693 |
| 26 | 3216930 |
| 27 | 6045851 |
| 28 | 11362482 |
| 29 | 21354481 |
| 30 | 40133296 |
| 31 | 75425924 |
| 32 | 141754368 |
| 33 | 266411067 |
| 34 | 500689027 |
[0,1,1,2,3,6,11,20,38,71,133,250,469,882,1657, 3114,5852,10998,20669,38845,73004,137203,257857, 484612,910773,1711693,3216930,6045851,11362482, 21354481,40133296,75425924,141754368,266411067, 500689027] |