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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 5 |
| 3 | 17 |
| 4 | 69 |
| 5 | 257 |
| 6 | 1045 |
| 7 | 4097 |
| 8 | 16453 |
| 9 | 65553 |
| 10 | 262405 |
| 11 | 1048577 |
| 12 | 4195413 |
| 13 | 16777217 |
| 14 | 67112965 |
| 15 | 268435729 |
| 16 | 1073758277 |
| 17 | 4294967297 |
| 18 | 17179935765 |
| 19 | 68719476737 |
| 20 | 274878169413 |
| 21 | 1099511631889 |
| 22 | 4398047559685 |
| 23 | 17592186044417 |
| 24 | 70368748389461 |
| 25 | 281474976710913 |
[1,5,17,69,257,1045,4097,16453,65553,262405, 1048577,4195413,16777217,67112965,268435729, 1073758277,4294967297,17179935765,68719476737, 274878169413,1099511631889,4398047559685, 17592186044417,70368748389461,281474976710913] |