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| n | a(n) |
|---|---|
| 0 | 3 |
| 1 | 17 |
| 2 | 81 |
| 3 | 367 |
| 4 | 1635 |
| 5 | 7241 |
| 6 | 32001 |
| 7 | 141319 |
| 8 | 623907 |
| 9 | 2754209 |
| 10 | 12157905 |
| 11 | 53667967 |
| 12 | 236902467 |
| 13 | 1045739033 |
| 14 | 4616116929 |
| 15 | 20376528343 |
| 16 | 89946351555 |
| 17 | 397042410929 |
| 18 | 1752630004689 |
| 19 | 7736483151631 |
| 20 | 34150488876963 |
| 21 | 150747551200361 |
| 22 | 665431885063425 |
| 23 | 2937358451978023 |
[3,17,81,367,1635,7241,32001,141319,623907, 2754209,12157905,53667967,236902467,1045739033, 4616116929,20376528343,89946351555,397042410929, 1752630004689,7736483151631,34150488876963, 150747551200361,665431885063425,2937358451978023] |