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| n | a(n) |
|---|---|
| 1 | 21 |
| 2 | 289 |
| 3 | 280 |
| 4 | 4370 |
| 5 | 34887 |
| 6 | 445745 |
| 7 | 9176798 |
| 8 | 160397426 |
| 9 | 2593742186 |
| 10 | 49371354839 |
| 11 | 908899582912 |
| 12 | 16074992228393 |
| 13 | 295578528424499 |
| 14 | 5422250103851024 |
| 15 | 98300554690294042 |
| 16 | 1794609057854976519 |
| 17 | 32811799818799674273 |
[21,289,280,4370,34887,445745,9176798,160397426, 2593742186,49371354839,908899582912, 16074992228393,295578528424499,5422250103851024, 98300554690294042,1794609057854976519, 32811799818799674273] |