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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 5 |
| 3 | 16 |
| 4 | 55 |
| 5 | 188 |
| 6 | 674 |
| 7 | 2471 |
| 8 | 9067 |
| 9 | 33926 |
| 10 | 128156 |
| 11 | 484224 |
| 12 | 1847218 |
| 13 | 7084777 |
| 14 | 27186054 |
| 15 | 104885416 |
| 16 | 405958461 |
| 17 | 1572023508 |
| 18 | 6108058902 |
| 19 | 23783305717 |
| 20 | 92648913045 |
| 21 | 361724652715 |
| 22 | 1414358846767 |
| 23 | 5532545855330 |
| 24 | 21675406458263 |
| 25 | 85011660185348 |
| 26 | 333545750611017 |
| 27 | 1310157468147696 |
| 28 | 5150459680441075 |
[1,2,5,16,55,188,674,2471,9067,33926,128156, 484224,1847218,7084777,27186054,104885416, 405958461,1572023508,6108058902,23783305717, 92648913045,361724652715,1414358846767, 5532545855330,21675406458263,85011660185348, 333545750611017,1310157468147696,5150459680441075] |