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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 15 |
| 5 | 38 |
| 6 | 126 |
| 7 | 403 |
| 8 | 1267 |
| 9 | 4364 |
| 10 | 15337 |
| 11 | 51008 |
| 12 | 186733 |
| 13 | 677566 |
| 14 | 2371655 |
| 15 | 8911984 |
| 16 | 33363459 |
| 17 | 120099472 |
| 18 | 461730365 |
| 19 | 1762385298 |
| 20 | 6489781432 |
| 21 | 25333729456 |
| 22 | 98240077694 |
| 23 | 367777089473 |
| 24 | 1453543853992 |
| 25 | 5704662375120 |
| 26 | 21642574662270 |
| 27 | 86368923368039 |
| 28 | 342309093506743 |
| 29 | 1312621073998531 |
| 30 | 5280365528689306 |
[1,1,2,5,15,38,126,403,1267,4364,15337,51008, 186733,677566,2371655,8911984,33363459,120099472, 461730365,1762385298,6489781432,25333729456, 98240077694,367777089473,1453543853992, 5704662375120,21642574662270,86368923368039, 342309093506743,1312621073998531,5280365528689306] |