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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 8 |
| 5 | 17 |
| 6 | 37 |
| 7 | 82 |
| 8 | 184 |
| 9 | 417 |
| 10 | 954 |
| 11 | 2200 |
| 12 | 5109 |
| 13 | 11937 |
| 14 | 28040 |
| 15 | 66179 |
| 16 | 156857 |
| 17 | 373205 |
| 18 | 891034 |
| 19 | 2134072 |
| 20 | 5125944 |
| 21 | 12344835 |
| 22 | 29802478 |
| 23 | 72109852 |
| 24 | 174839832 |
| 25 | 424742526 |
| 26 | 1033697149 |
| 27 | 2519947080 |
| 28 | 6152807700 |
| 29 | 15045156972 |
| 30 | 36840289213 |
| 31 | 90326900587 |
| 32 | 221741403579 |
| 33 | 544982530105 |
[1,1,2,4,8,17,37,82,184,417,954,2200,5109,11937, 28040,66179,156857,373205,891034,2134072,5125944, 12344835,29802478,72109852,174839832,424742526, 1033697149,2519947080,6152807700,15045156972, 36840289213,90326900587,221741403579,544982530105] |