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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 7 |
| 3 | 1 |
| 4 | 31 |
| 5 | 1 |
| 6 | 127 |
| 7 | 1 |
| 8 | 511 |
| 9 | 1 |
| 10 | 2047 |
| 11 | 1 |
| 12 | 8191 |
| 13 | 1 |
| 14 | 32767 |
| 15 | 1 |
| 16 | 131071 |
| 17 | 1 |
| 18 | 524287 |
| 19 | 1 |
| 20 | 2097151 |
| 21 | 1 |
| 22 | 8388607 |
| 23 | 1 |
| 24 | 33554431 |
| 25 | 1 |
| 26 | 134217727 |
| 27 | 1 |
| 28 | 536870911 |
| 29 | 1 |
| 30 | 2147483647 |
| 31 | 1 |
| 32 | 8589934591 |
| 33 | 1 |
| 34 | 34359738367 |
| 35 | 1 |
| 36 | 137438953471 |
| 37 | 1 |
| 38 | 549755813887 |
| 39 | 1 |
| 40 | 2199023255551 |
[1,1,7,1,31,1,127,1,511,1,2047,1,8191,1,32767,1, 131071,1,524287,1,2097151,1,8388607,1,33554431,1, 134217727,1,536870911,1,2147483647,1,8589934591,1, 34359738367,1,137438953471,1,549755813887,1, 2199023255551] |