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| n | a(n) |
|---|---|
| 1 | 69 |
| 2 | 488 |
| 3 | 1928 |
| 4 | 7494 |
| 5 | 27015 |
| 6 | 87621 |
| 7 | 319172 |
| 8 | 945613 |
| 9 | 2874539 |
| 10 | 6935762 |
| 11 | 22983454 |
| 12 | 49969332 |
| 13 | 119548267 |
| 14 | 214145613 |
| 15 | 622017082 |
| 16 | 1069718995 |
| 17 | 2070309209 |
| 18 | 3028231177 |
| 19 | 7700984072 |
| 20 | 11401562937 |
| 21 | 19017598555 |
| 22 | 24702675207 |
| 23 | 56114922678 |
| 24 | 75683326471 |
[69,488,1928,7494,27015,87621,319172,945613, 2874539,6935762,22983454,49969332,119548267, 214145613,622017082,1069718995,2070309209, 3028231177,7700984072,11401562937,19017598555, 24702675207,56114922678,75683326471] |