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| n | a(n) |
|---|---|
| 1 | 27 |
| 2 | 49 |
| 3 | 87 |
| 4 | 161 |
| 5 | 299 |
| 6 | 565 |
| 7 | 1075 |
| 8 | 2065 |
| 9 | 3991 |
| 10 | 7761 |
| 11 | 15163 |
| 12 | 29749 |
| 13 | 58563 |
| 14 | 115617 |
| 15 | 228791 |
| 16 | 453633 |
| 17 | 900875 |
| 18 | 1791413 |
| 19 | 3566099 |
| 20 | 7105137 |
| 21 | 14166487 |
| 22 | 28262129 |
| 23 | 56409627 |
| 24 | 112633781 |
| 25 | 224967459 |
| 26 | 449449345 |
| 27 | 898113015 |
| 28 | 1794954785 |
| 29 | 3587852651 |
[27,49,87,161,299,565,1075,2065,3991,7761,15163, 29749,58563,115617,228791,453633,900875,1791413, 3566099,7105137,14166487,28262129,56409627, 112633781,224967459,449449345,898113015, 1794954785,3587852651] |