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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 13 |
| 5 | 49 |
| 6 | 198 |
| 7 | 847 |
| 8 | 3796 |
| 9 | 17661 |
| 10 | 84754 |
| 11 | 417556 |
| 12 | 2104652 |
| 13 | 10825545 |
| 14 | 56714218 |
| 15 | 302185765 |
| 16 | 1635727560 |
| 17 | 8987357912 |
| 18 | 50090647729 |
| 19 | 283058794945 |
| 20 | 1621221821820 |
| 21 | 9409181197452 |
| 22 | 55327487031279 |
| 23 | 329591827614844 |
| 24 | 1989063796779401 |
[1,1,2,4,13,49,198,847,3796,17661,84754,417556, 2104652,10825545,56714218,302185765,1635727560, 8987357912,50090647729,283058794945,1621221821820, 9409181197452,55327487031279,329591827614844, 1989063796779401] |