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| n | a(n) |
|---|---|
| 0 | 2 |
| 1 | 4 |
| 2 | 7 |
| 3 | 12 |
| 4 | 20 |
| 5 | 34 |
| 6 | 58 |
| 7 | 99 |
| 8 | 169 |
| 9 | 288 |
| 10 | 491 |
| 11 | 837 |
| 12 | 1428 |
| 13 | 2437 |
| 14 | 4159 |
| 15 | 7099 |
| 16 | 12118 |
| 17 | 20686 |
| 18 | 35312 |
| 19 | 60280 |
| 20 | 102903 |
| 21 | 175665 |
| 22 | 299877 |
| 23 | 511920 |
| 24 | 873900 |
| 25 | 1491838 |
| 26 | 2546724 |
| 27 | 4347527 |
| 28 | 7421690 |
| 29 | 12669614 |
| 30 | 21628381 |
| 31 | 36921953 |
| 32 | 63029713 |
| 33 | 107598447 |
| 34 | 183682035 |
| 35 | 313564844 |
| 36 | 535288668 |
[2,4,7,12,20,34,58,99,169,288,491,837,1428,2437, 4159,7099,12118,20686,35312,60280,102903,175665, 299877,511920,873900,1491838,2546724,4347527, 7421690,12669614,21628381,36921953,63029713, 107598447,183682035,313564844,535288668] |