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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 8 |
| 3 | 41 |
| 4 | 232 |
| 5 | 1377 |
| 6 | 8399 |
| 7 | 52138 |
| 8 | 327656 |
| 9 | 2077934 |
| 10 | 13270633 |
| 11 | 85226594 |
| 12 | 549837391 |
| 13 | 3560702069 |
| 14 | 23132584742 |
| 15 | 150695482041 |
| 16 | 984021596136 |
| 17 | 6438849555963 |
| 18 | 42208999230224 |
| 19 | 277144740254566 |
| 20 | 1822379123910857 |
| 21 | 11998811140766701 |
| 22 | 79095365076843134 |
[1,2,8,41,232,1377,8399,52138,327656,2077934, 13270633,85226594,549837391,3560702069, 23132584742,150695482041,984021596136, 6438849555963,42208999230224,277144740254566, 1822379123910857,11998811140766701, 79095365076843134] |