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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 7 |
| 4 | 12 |
| 5 | 31 |
| 6 | 55 |
| 7 | 127 |
| 8 | 135 |
| 9 | 208 |
| 10 | 1095 |
| 11 | 8191 |
| 12 | 75447 |
| 13 | 131071 |
| 14 | 524287 |
| 15 | 1631620 |
| 16 | 2157040 |
| 17 | 2360955 |
| 18 | 2669567 |
| 19 | 7552768 |
| 20 | 9599551 |
| 21 | 12630271 |
| 22 | 13898863 |
| 23 | 18653559 |
| 24 | 19826143 |
| 25 | 20471807 |
| 26 | 62648191 |
| 27 | 64965199 |
| 28 | 155159388 |
| 29 | 455436287 |
| 30 | 900251647 |
| 31 | 1468363567 |
| 32 | 2147483647 |
| 33 | 2564808703 |
[1,3,7,12,31,55,127,135,208,1095,8191,75447, 131071,524287,1631620,2157040,2360955,2669567, 7552768,9599551,12630271,13898863,18653559, 19826143,20471807,62648191,64965199,155159388, 455436287,900251647,1468363567,2147483647, 2564808703] |