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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 11 |
| 2 | 70 |
| 3 | 348 |
| 4 | 1449 |
| 5 | 5334 |
| 6 | 17822 |
| 7 | 55165 |
| 8 | 160215 |
| 9 | 441105 |
| 10 | 1159752 |
| 11 | 2929465 |
| 12 | 7142275 |
| 13 | 16873472 |
| 14 | 38749850 |
| 15 | 86737678 |
| 16 | 189672868 |
| 17 | 405991500 |
| 18 | 852077072 |
| 19 | 1756048833 |
| 20 | 3558408287 |
| 21 | 7098041203 |
| 22 | 13951818365 |
| 23 | 27047831797 |
| 24 | 51760979985 |
[1,11,70,348,1449,5334,17822,55165,160215,441105, 1159752,2929465,7142275,16873472,38749850, 86737678,189672868,405991500,852077072,1756048833, 3558408287,7098041203,13951818365,27047831797, 51760979985] |