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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 15 |
| 5 | 39 |
| 6 | 127 |
| 7 | 405 |
| 8 | 1330 |
| 9 | 4478 |
| 10 | 15616 |
| 11 | 54421 |
| 12 | 194793 |
| 13 | 702460 |
| 14 | 2566274 |
| 15 | 9451947 |
| 16 | 35193820 |
| 17 | 131845947 |
| 18 | 497775471 |
| 19 | 1891195411 |
| 20 | 7227861089 |
| 21 | 27762928862 |
| 22 | 107200840091 |
| 23 | 415720406354 |
| 24 | 1619020483150 |
| 25 | 6329515027431 |
| 26 | 24836077599153 |
| 27 | 97777922664752 |
| 28 | 386164569404667 |
| 29 | 1529668930872126 |
| 30 | 6076165429767563 |
[1,1,2,5,15,39,127,405,1330,4478,15616,54421, 194793,702460,2566274,9451947,35193820,131845947, 497775471,1891195411,7227861089,27762928862, 107200840091,415720406354,1619020483150, 6329515027431,24836077599153,97777922664752, 386164569404667,1529668930872126,6076165429767563] |