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| n | a(n) |
|---|---|
| 1 | 81 |
| 2 | 253 |
| 3 | 759 |
| 4 | 2653 |
| 5 | 9273 |
| 6 | 34545 |
| 7 | 130067 |
| 8 | 502563 |
| 9 | 1957855 |
| 10 | 7707477 |
| 11 | 30479641 |
| 12 | 121049341 |
| 13 | 481805459 |
| 14 | 1921111559 |
| 15 | 7667874767 |
| 16 | 30628405561 |
| 17 | 122397615337 |
| 18 | 489285404561 |
| 19 | 1956323203363 |
| 20 | 7823125185531 |
| 21 | 31286692332191 |
| 22 | 125131311950285 |
[81,253,759,2653,9273,34545,130067,502563,1957855, 7707477,30479641,121049341,481805459,1921111559, 7667874767,30628405561,122397615337,489285404561, 1956323203363,7823125185531,31286692332191, 125131311950285] |