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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 14 |
| 5 | 43 |
| 6 | 144 |
| 7 | 525 |
| 8 | 2084 |
| 9 | 9005 |
| 10 | 42288 |
| 11 | 215111 |
| 12 | 1179738 |
| 13 | 6937765 |
| 14 | 43504598 |
| 15 | 289356385 |
| 16 | 2031636826 |
| 17 | 14995775647 |
| 18 | 115943399636 |
| 19 | 936138957225 |
| 20 | 7872233481696 |
| 21 | 68788474572625 |
| 22 | 623323010473012 |
| 23 | 5846701373312019 |
| 24 | 56677763478164422 |
| 25 | 567011396405398185 |
[1,1,2,5,14,43,144,525,2084,9005,42288,215111, 1179738,6937765,43504598,289356385,2031636826, 14995775647,115943399636,936138957225, 7872233481696,68788474572625,623323010473012, 5846701373312019,56677763478164422, 567011396405398185] |