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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 4 |
| 3 | 5 |
| 4 | 10 |
| 5 | 20 |
| 6 | 25 |
| 7 | 50 |
| 8 | 85 |
| 9 | 170 |
| 10 | 340 |
| 11 | 425 |
| 12 | 850 |
| 13 | 1385 |
| 14 | 3070 |
| 15 | 6140 |
| 16 | 10225 |
| 17 | 15335 |
| 18 | 29410 |
| 19 | 65135 |
| 20 | 129070 |
| 21 | 317675 |
| 22 | 1280860 |
| 23 | 2163725 |
| 24 | 3999775 |
| 25 | 7999550 |
| 26 | 20321515 |
| 27 | 81946460 |
| 28 | 138412045 |
| 29 | 255852575 |
| 30 | 511705150 |
| 31 | 1300234475 |
| 32 | 5242880860 |
[1,2,4,5,10,20,25,50,85,170,340,425,850,1385,3070, 6140,10225,15335,29410,65135,129070,317675, 1280860,2163725,3999775,7999550,20321515,81946460, 138412045,255852575,511705150,1300234475, 5242880860] |