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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 16 |
| 4 | 8388608 |
| 5 | 1532495540865888858358347027150309183618739122183602176 |
[1,2,16,8388608, 15324955408658888583583470271503091836187391221836\ 02176] |