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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 5 |
| 3 | 13 |
| 4 | 45 |
| 5 | 150 |
| 6 | 548 |
| 7 | 1895 |
| 8 | 7595 |
| 9 | 28565 |
| 10 | 115446 |
| 11 | 438694 |
| 12 | 1862878 |
| 13 | 7407410 |
| 14 | 31401854 |
| 15 | 125165643 |
| 16 | 548208863 |
| 17 | 2251065516 |
| 18 | 9811745632 |
| 19 | 40261665482 |
| 20 | 179765822208 |
| 21 | 753826837023 |
| 22 | 3345833966405 |
| 23 | 14001164979883 |
| 24 | 63337842696640 |
| 25 | 269572598312974 |
| 26 | 1211822937294886 |
| 27 | 5143408328423039 |
[1,2,5,13,45,150,548,1895,7595,28565,115446, 438694,1862878,7407410,31401854,125165643, 548208863,2251065516,9811745632,40261665482, 179765822208,753826837023,3345833966405, 14001164979883,63337842696640,269572598312974, 1211822937294886,5143408328423039] |