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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 8 |
| 3 | 31 |
| 4 | 136 |
| 5 | 595 |
| 6 | 2708 |
| 7 | 12422 |
| 8 | 57944 |
| 9 | 272047 |
| 10 | 1287966 |
| 11 | 6127908 |
| 12 | 29305248 |
| 13 | 140661334 |
| 14 | 677464577 |
| 15 | 3271799317 |
| 16 | 15840128961 |
| 17 | 76849014880 |
| 18 | 373533453669 |
| 19 | 1818569852770 |
| 20 | 8866788087181 |
| 21 | 43288177910845 |
| 22 | 211584687310466 |
| 23 | 1035288521940909 |
| 24 | 5070597363843572 |
| 25 | 24856524622025733 |
| 26 | 121947612958567187 |
[1,2,8,31,136,595,2708,12422,57944,272047,1287966, 6127908,29305248,140661334,677464577,3271799317, 15840128961,76849014880,373533453669, 1818569852770,8866788087181,43288177910845, 211584687310466,1035288521940909,5070597363843572, 24856524622025733,121947612958567187] |