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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 0 |
| 3 | 1 |
| 4 | 2 |
| 5 | 4 |
| 6 | 7 |
| 7 | 13 |
| 8 | 24 |
| 9 | 44 |
| 10 | 80 |
| 11 | 149 |
| 12 | 276 |
| 13 | 517 |
| 14 | 975 |
| 15 | 1852 |
| 16 | 3537 |
| 17 | 6775 |
| 18 | 13027 |
| 19 | 25128 |
| 20 | 48589 |
| 21 | 94151 |
| 22 | 182809 |
| 23 | 355553 |
| 24 | 692591 |
| 25 | 1350973 |
| 26 | 2638450 |
| 27 | 5158567 |
| 28 | 10096032 |
| 29 | 19777579 |
| 30 | 38775771 |
| 31 | 76082812 |
| 32 | 149390879 |
| 33 | 293528094 |
| 34 | 577088731 |
| 35 | 1135234401 |
[0,0,0,1,2,4,7,13,24,44,80,149,276,517,975,1852, 3537,6775,13027,25128,48589,94151,182809,355553, 692591,1350973,2638450,5158567,10096032,19777579, 38775771,76082812,149390879,293528094,577088731, 1135234401] |