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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 12 |
| 3 | 57 |
| 4 | 283 |
| 5 | 1415 |
| 6 | 7097 |
| 7 | 35513 |
| 8 | 177572 |
| 9 | 887845 |
| 10 | 4438957 |
| 11 | 22194651 |
| 12 | 110973054 |
| 13 | 554865069 |
| 14 | 2774325211 |
| 15 | 13871626055 |
| 16 | 69358131749 |
| 17 | 346790660621 |
| 18 | 1733953303574 |
| 19 | 8669766516865 |
| 20 | 43348832566369 |
| 21 | 216744162822867 |
| 22 | 1083720814100868 |
[3,12,57,283,1415,7097,35513,177572,887845, 4438957,22194651,110973054,554865069,2774325211, 13871626055,69358131749,346790660621, 1733953303574,8669766516865,43348832566369, 216744162822867,1083720814100868] |