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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 3 |
| 7 | 4 |
| 8 | 6 |
| 9 | 15 |
| 10 | 28 |
| 11 | 56 |
| 12 | 125 |
| 13 | 287 |
| 14 | 646 |
| 15 | 1540 |
| 16 | 3625 |
| 17 | 8484 |
| 18 | 21167 |
| 19 | 51458 |
| 20 | 126342 |
| 21 | 323126 |
| 22 | 811538 |
| 23 | 2052501 |
| 24 | 5339265 |
| 25 | 13751212 |
| 26 | 35589866 |
| 27 | 94032931 |
| 28 | 246791641 |
| 29 | 650227636 |
| 30 | 1739032299 |
| 31 | 4630165425 |
| 32 | 12373805281 |
| 33 | 33429284691 |
| 34 | 90073865814 |
| 35 | 243460560324 |
[0,1,1,1,1,1,3,4,6,15,28,56,125,287,646,1540,3625, 8484,21167,51458,126342,323126,811538,2052501, 5339265,13751212,35589866,94032931,246791641, 650227636,1739032299,4630165425,12373805281, 33429284691,90073865814,243460560324] |