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| n | a(n) |
|---|---|
| 0 | 4 |
| 1 | 25 |
| 2 | 193 |
| 3 | 1537 |
| 4 | 12289 |
| 5 | 98305 |
| 6 | 786433 |
| 7 | 6291457 |
| 8 | 50331649 |
| 9 | 402653185 |
| 10 | 3221225473 |
| 11 | 25769803777 |
| 12 | 206158430209 |
| 13 | 1649267441665 |
| 14 | 13194139533313 |
| 15 | 105553116266497 |
| 16 | 844424930131969 |
| 17 | 6755399441055745 |
| 18 | 54043195528445953 |
[4,25,193,1537,12289,98305,786433,6291457, 50331649,402653185,3221225473,25769803777, 206158430209,1649267441665,13194139533313, 105553116266497,844424930131969,6755399441055745, 54043195528445953] |