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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 8 |
| 3 | 31 |
| 4 | 142 |
| 5 | 613 |
| 6 | 2911 |
| 7 | 13254 |
| 8 | 64103 |
| 9 | 300048 |
| 10 | 1465700 |
| 11 | 6979549 |
| 12 | 34308642 |
| 13 | 165223123 |
| 14 | 815532129 |
| 15 | 3958572282 |
| 16 | 19595889988 |
| 17 | 95663500938 |
| 18 | 474546185421 |
| 19 | 2326630508074 |
| 20 | 11559382601418 |
| 21 | 56861362785924 |
| 22 | 282837917817341 |
| 23 | 1394911664094147 |
| 24 | 6944889676788391 |
| 25 | 34322010181893270 |
| 26 | 171003473530937424 |
[1,2,8,31,142,613,2911,13254,64103,300048,1465700, 6979549,34308642,165223123,815532129,3958572282, 19595889988,95663500938,474546185421, 2326630508074,11559382601418,56861362785924, 282837917817341,1394911664094147,6944889676788391, 34322010181893270,171003473530937424] |