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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 19 |
| 5 | 61 |
| 6 | 231 |
| 7 | 829 |
| 8 | 3411 |
| 9 | 13174 |
| 10 | 55582 |
| 11 | 224050 |
| 12 | 967760 |
| 13 | 4025392 |
| 14 | 17659214 |
| 15 | 75079047 |
| 16 | 333251508 |
| 17 | 1441084386 |
| 18 | 6455852339 |
| 19 | 28282925801 |
| 20 | 127631409983 |
| 21 | 565049348637 |
| 22 | 2565238396179 |
| 23 | 11453873093860 |
| 24 | 52258674096405 |
| 25 | 234993625412768 |
| 26 | 1076697344305840 |
| 27 | 4870486794682944 |
| 28 | 22396424337542850 |
[1,1,2,5,19,61,231,829,3411,13174,55582,224050, 967760,4025392,17659214,75079047,333251508, 1441084386,6455852339,28282925801,127631409983, 565049348637,2565238396179,11453873093860, 52258674096405,234993625412768,1076697344305840, 4870486794682944,22396424337542850] |