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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 7 |
| 3 | 31 |
| 4 | 127 |
| 5 | 23 |
| 6 | 89 |
| 7 | 8191 |
| 8 | 131071 |
| 9 | 524287 |
| 10 | 47 |
| 11 | 178481 |
| 12 | 233 |
| 13 | 1103 |
| 14 | 2089 |
| 15 | 2147483647 |
| 16 | 223 |
| 17 | 616318177 |
| 18 | 13367 |
| 19 | 164511353 |
| 20 | 431 |
| 21 | 9719 |
| 22 | 2099863 |
| 23 | 2351 |
| 24 | 4513 |
| 25 | 13264529 |
| 26 | 6361 |
| 27 | 69431 |
| 28 | 20394401 |
| 29 | 179951 |
| 30 | 3203431780337 |
| 31 | 2305843009213693951 |
| 32 | 193707721 |
| 33 | 761838257287 |
[3,7,31,127,23,89,8191,131071,524287,47,178481, 233,1103,2089,2147483647,223,616318177,13367, 164511353,431,9719,2099863,2351,4513,13264529, 6361,69431,20394401,179951,3203431780337, 2305843009213693951,193707721,761838257287] |