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| n | a(n) |
|---|---|
| 1 | 2221 |
| 2 | 6344 |
| 3 | 17889 |
| 4 | 55849 |
| 5 | 189092 |
| 6 | 651914 |
| 7 | 2136068 |
| 8 | 7213362 |
| 9 | 24711312 |
| 10 | 83529368 |
| 11 | 282700608 |
| 12 | 962444038 |
| 13 | 3267244950 |
| 14 | 11083453896 |
| 15 | 37685135612 |
| 16 | 128025816414 |
| 17 | 434507040386 |
| 18 | 1476562881230 |
| 19 | 5017650387416 |
| 20 | 17036610075740 |
| 21 | 57869261660158 |
[2221,6344,17889,55849,189092,651914,2136068, 7213362,24711312,83529368,282700608,962444038, 3267244950,11083453896,37685135612,128025816414, 434507040386,1476562881230,5017650387416, 17036610075740,57869261660158] |