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| n | a(n) |
|---|---|
| 1 | 9 |
| 2 | 81 |
| 3 | 361 |
| 4 | 1849 |
| 5 | 10201 |
| 6 | 58081 |
| 7 | 335241 |
| 8 | 1946025 |
| 9 | 11323225 |
| 10 | 65950641 |
| 11 | 384277609 |
| 12 | 2239466329 |
| 13 | 13051920025 |
| 14 | 76070604481 |
| 15 | 443368207881 |
| 16 | 2584130195529 |
| 17 | 15061392571801 |
| 18 | 87784176001041 |
| 19 | 511643544572521 |
| 20 | 2982076804476025 |
[9,81,361,1849,10201,58081,335241,1946025, 11323225,65950641,384277609,2239466329, 13051920025,76070604481,443368207881, 2584130195529,15061392571801,87784176001041, 511643544572521,2982076804476025] |