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| n | a(n) |
|---|---|
| 0 | 11 |
| 1 | 30 |
| 2 | 105 |
| 3 | 426 |
| 4 | 1940 |
| 5 | 9722 |
| 6 | 52902 |
| 7 | 309546 |
| 8 | 1933171 |
| 9 | 12809264 |
| 10 | 89613587 |
| 11 | 659255660 |
| 12 | 5082342477 |
| 13 | 40936552022 |
| 14 | 343612396821 |
| 15 | 2998777788602 |
| 16 | 27155414911274 |
| 17 | 254692965196866 |
| 18 | 2470107851719160 |
| 19 | 24734913573251578 |
| 20 | 255396574564032443 |
| 21 | 2715780007867965824 |
[11,30,105,426,1940,9722,52902,309546,1933171, 12809264,89613587,659255660,5082342477, 40936552022,343612396821,2998777788602, 27155414911274,254692965196866,2470107851719160, 24734913573251578,255396574564032443, 2715780007867965824] |