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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 14 |
| 5 | 42 |
| 6 | 134 |
| 7 | 450 |
| 8 | 1561 |
| 9 | 5584 |
| 10 | 20384 |
| 11 | 76110 |
| 12 | 288678 |
| 13 | 1111867 |
| 14 | 4332969 |
| 15 | 17081566 |
| 16 | 68003151 |
| 17 | 273141366 |
| 18 | 1105621792 |
| 19 | 4507122693 |
| 20 | 18493763341 |
| 21 | 76333387299 |
| 22 | 316764690900 |
| 23 | 1320956750386 |
| 24 | 5533915084459 |
| 25 | 23281928699430 |
| 26 | 98335287674627 |
| 27 | 416846016334321 |
| 28 | 1773046351548880 |
| 29 | 7565766894106024 |
[1,1,2,5,14,42,134,450,1561,5584,20384,76110, 288678,1111867,4332969,17081566,68003151, 273141366,1105621792,4507122693,18493763341, 76333387299,316764690900,1320956750386, 5533915084459,23281928699430,98335287674627, 416846016334321,1773046351548880,7565766894106024] |