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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 5 |
| 3 | 17 |
| 4 | 257 |
| 5 | 46657 |
| 6 | 65537 |
| 7 | 148997 |
| 8 | 67371265 |
| 9 | 405458497 |
| 10 | 1370776577 |
| 11 | 3497539601 |
| 12 | 4294967297 |
| 13 | 80542440001 |
| 14 | 422240040001 |
| 15 | 1911029760001 |
| 16 | 139251776898727937 |
| 17 | 286245437364810001 |
| 18 | 6017402415698251777 |
| 19 | 18446744073709551617 |
[1,5,17,257,46657,65537,148997,67371265,405458497, 1370776577,3497539601,4294967297,80542440001, 422240040001,1911029760001,139251776898727937, 286245437364810001,6017402415698251777, 18446744073709551617] |