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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 5 |
| 3 | 14 |
| 4 | 43 |
| 5 | 142 |
| 6 | 497 |
| 7 | 1828 |
| 8 | 7037 |
| 9 | 28326 |
| 10 | 119361 |
| 11 | 527748 |
| 12 | 2454929 |
| 13 | 12041410 |
| 14 | 62354641 |
| 15 | 340840118 |
| 16 | 1963757863 |
| 17 | 11896370734 |
| 18 | 75549183725 |
| 19 | 501393978466 |
| 20 | 3467199478543 |
| 21 | 24916100775758 |
| 22 | 185646100106929 |
| 23 | 1431332539961350 |
[1,2,5,14,43,142,497,1828,7037,28326,119361, 527748,2454929,12041410,62354641,340840118, 1963757863,11896370734,75549183725,501393978466, 3467199478543,24916100775758,185646100106929, 1431332539961350] |