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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 9 |
| 3 | 39 |
| 4 | 183 |
| 5 | 833 |
| 6 | 3629 |
| 7 | 15291 |
| 8 | 63051 |
| 9 | 256605 |
| 10 | 1036401 |
| 11 | 4167815 |
| 12 | 16720031 |
| 13 | 66986169 |
| 14 | 268173525 |
| 15 | 1073185011 |
| 16 | 4293787923 |
| 17 | 17177379125 |
| 18 | 68714234201 |
| 19 | 274866897279 |
| 20 | 1099488559527 |
| 21 | 4397998277073 |
| 22 | 17592085381629 |
| 23 | 70368534463019 |
| 24 | 281474540503643 |
| 25 | 1125899000873613 |
[3,9,39,183,833,3629,15291,63051,256605,1036401, 4167815,16720031,66986169,268173525,1073185011, 4293787923,17177379125,68714234201,274866897279, 1099488559527,4397998277073,17592085381629, 70368534463019,281474540503643,1125899000873613] |