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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 257 |
| 3 | 6562 |
| 4 | 65537 |
| 5 | 390626 |
| 6 | 1686434 |
| 7 | 5764802 |
| 8 | 16777217 |
| 9 | 43046722 |
| 10 | 100390882 |
| 11 | 214358882 |
| 12 | 430053794 |
| 13 | 815730722 |
| 14 | 1481554114 |
| 15 | 2563287812 |
| 16 | 4294967297 |
| 17 | 6975757442 |
| 18 | 11063007554 |
| 19 | 16983563042 |
| 20 | 25600456162 |
| 21 | 37828630724 |
[1,257,6562,65537,390626,1686434,5764802,16777217, 43046722,100390882,214358882,430053794,815730722, 1481554114,2563287812,4294967297,6975757442, 11063007554,16983563042,25600456162,37828630724] |