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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 10 |
| 3 | 42 |
| 4 | 182 |
| 5 | 790 |
| 6 | 3432 |
| 7 | 14914 |
| 8 | 64814 |
| 9 | 281680 |
| 10 | 1224182 |
| 11 | 5320310 |
| 12 | 23122148 |
| 13 | 100489226 |
| 14 | 436727814 |
| 15 | 1898026232 |
| 16 | 8248853134 |
| 17 | 35849651070 |
| 18 | 155803171860 |
| 19 | 677123141810 |
| 20 | 2942788286798 |
| 21 | 12789406189672 |
| 22 | 55582969192486 |
| 23 | 241564496305670 |
| 24 | 1049843265359828 |
[1,2,10,42,182,790,3432,14914,64814,281680, 1224182,5320310,23122148,100489226,436727814, 1898026232,8248853134,35849651070,155803171860, 677123141810,2942788286798,12789406189672, 55582969192486,241564496305670,1049843265359828] |