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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 7 |
| 3 | 127 |
| 4 | 511 |
| 5 | 8191 |
| 6 | 32767 |
| 7 | 2097151 |
| 8 | 33554431 |
| 9 | 2147483647 |
| 10 | 8589934591 |
| 11 | 137438953471 |
| 12 | 8796093022207 |
| 13 | 562949953421311 |
| 14 | 2251799813685247 |
| 15 | 9223372036854775807 |
| 16 | 147573952589676412927 |
| 17 | 590295810358705651711 |
| 18 | 9444732965739290427391 |
| 19 | 37778931862957161709567 |
[1,7,127,511,8191,32767,2097151,33554431, 2147483647,8589934591,137438953471,8796093022207, 562949953421311,2251799813685247, 9223372036854775807,147573952589676412927, 590295810358705651711,9444732965739290427391, 37778931862957161709567] |