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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 6 |
| 3 | 30 |
| 4 | 126 |
| 5 | 510 |
| 6 | 2046 |
| 7 | 7935 |
| 8 | 32767 |
| 9 | 196607 |
| 10 | 524286 |
| 11 | 2031615 |
| 12 | 8323071 |
| 13 | 50331647 |
| 14 | 134217723 |
| 15 | 535822335 |
| 16 | 2143289343 |
| 17 | 8573157375 |
| 18 | 66571993087 |
| 19 | 103079215103 |
| 20 | 549755813887 |
| 21 | 2164663517183 |
| 22 | 8796093022207 |
| 23 | 35184372088831 |
| 24 | 140737488355327 |
| 25 | 558551906910207 |
| 26 | 2250700302057471 |
[1,6,30,126,510,2046,7935,32767,196607,524286, 2031615,8323071,50331647,134217723,535822335, 2143289343,8573157375,66571993087,103079215103, 549755813887,2164663517183,8796093022207, 35184372088831,140737488355327,558551906910207, 2250700302057471] |