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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 8 |
| 3 | 28 |
| 4 | 118 |
| 5 | 483 |
| 6 | 2092 |
| 7 | 9140 |
| 8 | 40607 |
| 9 | 182856 |
| 10 | 830045 |
| 11 | 3801482 |
| 12 | 17532669 |
| 13 | 81271892 |
| 14 | 378987884 |
| 15 | 1773793791 |
| 16 | 8337879685 |
| 17 | 39323503292 |
| 18 | 186018296095 |
| 19 | 882541787862 |
| 20 | 4196985933172 |
| 21 | 20006531011962 |
| 22 | 95564810324894 |
| 23 | 457342866323809 |
| 24 | 2192643898947722 |
| 25 | 10528758533871823 |
| 26 | 50634865005630297 |
| 27 | 243849648904635955 |
[1,2,8,28,118,483,2092,9140,40607,182856,830045, 3801482,17532669,81271892,378987884,1773793791, 8337879685,39323503292,186018296095,882541787862, 4196985933172,20006531011962,95564810324894, 457342866323809,2192643898947722, 10528758533871823,50634865005630297, 243849648904635955] |