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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 19 |
| 5 | 63 |
| 6 | 233 |
| 7 | 881 |
| 8 | 3454 |
| 9 | 13895 |
| 10 | 56957 |
| 11 | 237185 |
| 12 | 1001514 |
| 13 | 4274113 |
| 14 | 18421481 |
| 15 | 80049553 |
| 16 | 350339864 |
| 17 | 1543114276 |
| 18 | 6834599858 |
| 19 | 30421512784 |
| 20 | 136016594930 |
| 21 | 610563182006 |
| 22 | 2750696838904 |
| 23 | 12433236054068 |
| 24 | 56366827142938 |
| 25 | 256245427672152 |
| 26 | 1167838731186473 |
| 27 | 5334787378301284 |
| 28 | 24422180784557641 |
[1,1,2,6,19,63,233,881,3454,13895,56957,237185, 1001514,4274113,18421481,80049553,350339864, 1543114276,6834599858,30421512784,136016594930, 610563182006,2750696838904,12433236054068, 56366827142938,256245427672152,1167838731186473, 5334787378301284,24422180784557641] |