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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 9 |
| 3 | 49 |
| 4 | 289 |
| 5 | 1681 |
| 6 | 9801 |
| 7 | 57121 |
| 8 | 332929 |
| 9 | 1940449 |
| 10 | 11309769 |
| 11 | 65918161 |
| 12 | 384199201 |
| 13 | 2239277041 |
| 14 | 13051463049 |
| 15 | 76069501249 |
| 16 | 443365544449 |
| 17 | 2584123765441 |
| 18 | 15061377048201 |
| 19 | 87784138523761 |
| 20 | 511643454094369 |
| 21 | 2982076586042449 |
| 22 | 17380816062160329 |
| 23 | 101302819786919521 |
| 24 | 590436102659356801 |
[1,1,9,49,289,1681,9801,57121,332929,1940449, 11309769,65918161,384199201,2239277041, 13051463049,76069501249,443365544449, 2584123765441,15061377048201,87784138523761, 511643454094369,2982076586042449, 17380816062160329,101302819786919521, 590436102659356801] |