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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 6 |
| 5 | 14 |
| 6 | 44 |
| 7 | 132 |
| 8 | 434 |
| 9 | 1431 |
| 10 | 4876 |
| 11 | 16796 |
| 12 | 58831 |
| 13 | 208012 |
| 14 | 743032 |
| 15 | 2674449 |
| 16 | 9695275 |
| 17 | 35357670 |
| 18 | 129646248 |
| 19 | 477638700 |
| 20 | 1767268056 |
| 21 | 6564120510 |
| 22 | 24466283816 |
| 23 | 91482563640 |
| 24 | 343059672747 |
| 25 | 1289904147325 |
| 26 | 4861946609464 |
| 27 | 18367353073153 |
| 28 | 69533551658952 |
| 29 | 263747951750360 |
| 30 | 1002242219329245 |
| 31 | 3814986502092304 |
| 32 | 14544636048921919 |
| 33 | 55534064877060132 |
| 34 | 212336130447600780 |
[1,1,1,2,6,14,44,132,434,1431,4876,16796,58831, 208012,743032,2674449,9695275,35357670,129646248, 477638700,1767268056,6564120510,24466283816, 91482563640,343059672747,1289904147325, 4861946609464,18367353073153,69533551658952, 263747951750360,1002242219329245,3814986502092304, 14544636048921919,55534064877060132, 212336130447600780] |