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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 11 |
| 3 | 47 |
| 4 | 221 |
| 5 | 1433 |
| 6 | 9579 |
| 7 | 69044 |
| 8 | 519260 |
| 9 | 4056919 |
| 10 | 32504975 |
| 11 | 266490184 |
| 12 | 2224590493 |
| 13 | 18850792161 |
[3,11,47,221,1433,9579,69044,519260,4056919, 32504975,266490184,2224590493,18850792161] |