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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 5 |
| 3 | 15 |
| 4 | 49 |
| 5 | 165 |
| 6 | 584 |
| 7 | 2134 |
| 8 | 7902 |
| 9 | 29892 |
| 10 | 114882 |
| 11 | 445389 |
| 12 | 1746830 |
| 13 | 6917227 |
| 14 | 27555548 |
| 15 | 110577812 |
| 16 | 446571878 |
| 17 | 1811419809 |
| 18 | 7384904017 |
| 19 | 30243833998 |
| 20 | 124275887253 |
| 21 | 512565470691 |
| 22 | 2121206098773 |
| 23 | 8801749477275 |
| 24 | 36626130235013 |
| 25 | 152811471519802 |
| 26 | 638933029743026 |
| 27 | 2677526963798012 |
[1,2,5,15,49,165,584,2134,7902,29892,114882, 445389,1746830,6917227,27555548,110577812, 446571878,1811419809,7384904017,30243833998, 124275887253,512565470691,2121206098773, 8801749477275,36626130235013,152811471519802, 638933029743026,2677526963798012] |