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| n | a(n) |
|---|---|
| 1 | 234 |
| 2 | 810 |
| 3 | 2978 |
| 4 | 10154 |
| 5 | 34894 |
| 6 | 120474 |
| 7 | 413478 |
| 8 | 1423482 |
| 9 | 4910062 |
| 10 | 16902314 |
| 11 | 58156234 |
| 12 | 200254002 |
| 13 | 689660322 |
| 14 | 2374561330 |
| 15 | 8175197942 |
| 16 | 28147732742 |
| 17 | 96918297378 |
| 18 | 333703130278 |
| 19 | 1148964344370 |
| 20 | 3955983666942 |
| 21 | 13620906393306 |
[234,810,2978,10154,34894,120474,413478,1423482, 4910062,16902314,58156234,200254002,689660322, 2374561330,8175197942,28147732742,96918297378, 333703130278,1148964344370,3955983666942, 13620906393306] |