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| n | a(n) |
|---|---|
| 0 | 7 |
| 1 | 33 |
| 2 | 85 |
| 3 | 189 |
| 4 | 397 |
| 5 | 813 |
| 6 | 1645 |
| 7 | 3309 |
| 8 | 6637 |
| 9 | 13293 |
| 10 | 26605 |
| 11 | 53229 |
| 12 | 106477 |
| 13 | 212973 |
| 14 | 425965 |
| 15 | 851949 |
| 16 | 1703917 |
| 17 | 3407853 |
| 18 | 6815725 |
| 19 | 13631469 |
| 20 | 27262957 |
| 21 | 54525933 |
| 22 | 109051885 |
| 23 | 218103789 |
| 24 | 436207597 |
| 25 | 872415213 |
| 26 | 1744830445 |
| 27 | 3489660909 |
| 28 | 6979321837 |
| 29 | 13958643693 |
[7,33,85,189,397,813,1645,3309,6637,13293,26605, 53229,106477,212973,425965,851949,1703917,3407853, 6815725,13631469,27262957,54525933,109051885, 218103789,436207597,872415213,1744830445, 3489660909,6979321837,13958643693] |