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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 7 |
| 3 | 24 |
| 4 | 102 |
| 5 | 417 |
| 6 | 1870 |
| 7 | 8084 |
| 8 | 37470 |
| 9 | 168965 |
| 10 | 794731 |
| 11 | 3654241 |
| 12 | 17409564 |
| 13 | 81476048 |
| 14 | 390757848 |
| 15 | 1846159739 |
| 16 | 8911674092 |
| 17 | 42495832330 |
| 18 | 205901393430 |
| 19 | 987251611544 |
| 20 | 4801802056122 |
| 21 | 23152006338312 |
| 22 | 112876113393819 |
| 23 | 546156268722029 |
| 24 | 2669431334997184 |
| 25 | 12963330205039792 |
| 26 | 63465753054060682 |
| 27 | 308954533070833734 |
[1,2,7,24,102,417,1870,8084,37470,168965,794731, 3654241,17409564,81476048,390757848,1846159739, 8911674092,42495832330,205901393430,987251611544, 4801802056122,23152006338312,112876113393819, 546156268722029,2669431334997184, 12963330205039792,63465753054060682, 308954533070833734] |