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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 14 |
| 5 | 38 |
| 6 | 96 |
| 7 | 256 |
| 8 | 672 |
| 9 | 1805 |
| 10 | 4846 |
| 11 | 13162 |
| 12 | 35874 |
| 13 | 98469 |
| 14 | 271384 |
| 15 | 751656 |
| 16 | 2089640 |
| 17 | 5831451 |
| 18 | 16325950 |
| 19 | 45847770 |
| 20 | 129106738 |
| 21 | 364498596 |
| 22 | 1031480792 |
| 23 | 2925337352 |
| 24 | 8313200232 |
| 25 | 23668977163 |
| 26 | 67507731786 |
| 27 | 192859753310 |
| 28 | 551821286374 |
| 29 | 1581188102590 |
[0,1,2,6,14,38,96,256,672,1805,4846,13162,35874, 98469,271384,751656,2089640,5831451,16325950, 45847770,129106738,364498596,1031480792, 2925337352,8313200232,23668977163,67507731786, 192859753310,551821286374,1581188102590] |