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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 6 |
| 3 | 14 |
| 4 | 15 |
| 5 | 55 |
| 6 | 63 |
| 7 | 247 |
| 8 | 255 |
| 9 | 511 |
| 10 | 1023 |
| 11 | 2047 |
| 12 | 4095 |
| 13 | 12287 |
| 14 | 16383 |
| 15 | 32767 |
| 16 | 65535 |
| 17 | 196607 |
| 18 | 262143 |
| 19 | 983039 |
| 20 | 1048575 |
| 21 | 2097151 |
| 22 | 4194303 |
| 23 | 8388607 |
| 24 | 16777215 |
| 25 | 33554431 |
| 26 | 67108863 |
| 27 | 134217727 |
| 28 | 268435455 |
| 29 | 536870911 |
| 30 | 1073741823 |
| 31 | 3221225471 |
[1,6,14,15,55,63,247,255,511,1023,2047,4095,12287, 16383,32767,65535,196607,262143,983039,1048575, 2097151,4194303,8388607,16777215,33554431, 67108863,134217727,268435455,536870911,1073741823, 3221225471] |