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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 5 |
| 3 | 17 |
| 4 | 66 |
| 5 | 274 |
| 6 | 1190 |
| 7 | 5341 |
| 8 | 24577 |
| 9 | 115326 |
| 10 | 549747 |
| 11 | 2654739 |
| 12 | 12959468 |
| 13 | 63848307 |
| 14 | 317064921 |
| 15 | 1585380283 |
| 16 | 7975134892 |
| 17 | 40332823042 |
| 18 | 204947059412 |
| 19 | 1045859173864 |
| 20 | 5357606584326 |
| 21 | 27540884494209 |
| 22 | 142023060613755 |
| 23 | 734506610474205 |
| 24 | 3808771672620618 |
| 25 | 19798640525731461 |
| 26 | 103149287155802941 |
[1,2,5,17,66,274,1190,5341,24577,115326,549747, 2654739,12959468,63848307,317064921,1585380283, 7975134892,40332823042,204947059412,1045859173864, 5357606584326,27540884494209,142023060613755, 734506610474205,3808771672620618, 19798640525731461,103149287155802941] |