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| n | a(n) |
|---|---|
| 1 | 7 |
| 2 | 15 |
| 3 | 31 |
| 4 | 64 |
| 5 | 129 |
| 6 | 258 |
| 7 | 515 |
| 8 | 1029 |
| 9 | 2055 |
| 10 | 4107 |
| 11 | 8211 |
| 12 | 16410 |
| 13 | 32811 |
| 14 | 65624 |
| 15 | 131224 |
| 16 | 262372 |
| 17 | 524634 |
| 18 | 1049237 |
| 19 | 2098363 |
| 20 | 4196161 |
| 21 | 8391728 |
| 22 | 16783688 |
| 23 | 33567165 |
| 24 | 67128918 |
| 25 | 134250383 |
| 26 | 268502449 |
| 27 | 536999938 |
| 28 | 1073948247 |
| 29 | 2147837919 |
| 30 | 4295732271 |
[7,15,31,64,129,258,515,1029,2055,4107,8211,16410, 32811,65624,131224,262372,524634,1049237,2098363, 4196161,8391728,16783688,33567165,67128918, 134250383,268502449,536999938,1073948247, 2147837919,4295732271] |