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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 17 |
| 5 | 56 |
| 6 | 204 |
| 7 | 779 |
| 8 | 3083 |
| 9 | 12542 |
| 10 | 51867 |
| 11 | 218851 |
| 12 | 937428 |
| 13 | 4066279 |
| 14 | 17819039 |
| 15 | 78771159 |
| 16 | 351148071 |
| 17 | 1576762625 |
| 18 | 7124754861 |
| 19 | 32369976554 |
| 20 | 147797541104 |
| 21 | 677966771333 |
| 22 | 3123008282073 |
| 23 | 14439960175164 |
| 24 | 66992611362021 |
| 25 | 311781381899059 |
| 26 | 1455300136591569 |
| 27 | 6811383379597123 |
| 28 | 31959257776835476 |
[1,1,2,5,17,56,204,779,3083,12542,51867,218851, 937428,4066279,17819039,78771159,351148071, 1576762625,7124754861,32369976554,147797541104, 677966771333,3123008282073,14439960175164, 66992611362021,311781381899059,1455300136591569, 6811383379597123,31959257776835476] |