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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 8 |
| 4 | 26 |
| 5 | 82 |
| 6 | 285 |
| 7 | 995 |
| 8 | 3613 |
| 9 | 13319 |
| 10 | 50053 |
| 11 | 190459 |
| 12 | 733555 |
| 13 | 2851945 |
| 14 | 11181927 |
| 15 | 44155907 |
| 16 | 175470374 |
| 17 | 701164361 |
| 18 | 2815635000 |
| 19 | 11356456980 |
| 20 | 45986353012 |
| 21 | 186882752814 |
| 22 | 761942170718 |
| 23 | 3115758466971 |
| 24 | 12775760835540 |
| 25 | 52516539411929 |
| 26 | 216375430357044 |
| 27 | 893403847582583 |
[1,1,3,8,26,82,285,995,3613,13319,50053,190459, 733555,2851945,11181927,44155907,175470374, 701164361,2815635000,11356456980,45986353012, 186882752814,761942170718,3115758466971, 12775760835540,52516539411929,216375430357044, 893403847582583] |