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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 6 |
| 3 | 22 |
| 4 | 82 |
| 5 | 329 |
| 6 | 1356 |
| 7 | 5728 |
| 8 | 24771 |
| 9 | 108333 |
| 10 | 480976 |
| 11 | 2155838 |
| 12 | 9745021 |
| 13 | 44411257 |
| 14 | 203558361 |
| 15 | 938658857 |
| 16 | 4349164000 |
| 17 | 20238009107 |
| 18 | 94557029374 |
| 19 | 443272736527 |
| 20 | 2084784929706 |
| 21 | 9832969315029 |
| 22 | 46497685752388 |
| 23 | 220411927241557 |
| 24 | 1047065731564630 |
| 25 | 4984265950513456 |
| 26 | 23770506968527747 |
| 27 | 113559811107454136 |
[1,2,6,22,82,329,1356,5728,24771,108333,480976, 2155838,9745021,44411257,203558361,938658857, 4349164000,20238009107,94557029374,443272736527, 2084784929706,9832969315029,46497685752388, 220411927241557,1047065731564630,4984265950513456, 23770506968527747,113559811107454136] |