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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 3 |
| 4 | 6 |
| 5 | 14 |
| 6 | 32 |
| 7 | 79 |
| 8 | 203 |
| 9 | 541 |
| 10 | 1495 |
| 11 | 4267 |
| 12 | 12543 |
| 13 | 37902 |
| 14 | 117519 |
| 15 | 373236 |
| 16 | 1212418 |
| 17 | 4023007 |
| 18 | 13619993 |
| 19 | 46998318 |
| 20 | 165144243 |
| 21 | 590411905 |
| 22 | 2145978422 |
| 23 | 7924484313 |
| 24 | 29710783080 |
| 25 | 113031311232 |
| 26 | 436102652463 |
| 27 | 1705552475812 |
| 28 | 6758097531570 |
| 29 | 27119230158894 |
[1,1,1,3,6,14,32,79,203,541,1495,4267,12543,37902, 117519,373236,1212418,4023007,13619993,46998318, 165144243,590411905,2145978422,7924484313, 29710783080,113031311232,436102652463, 1705552475812,6758097531570,27119230158894] |