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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 11 |
| 4 | 49 |
| 5 | 157 |
| 6 | 681 |
| 7 | 2371 |
| 8 | 10745 |
| 9 | 39323 |
| 10 | 179183 |
| 11 | 689829 |
| 12 | 3166221 |
| 13 | 12438603 |
| 14 | 57683523 |
| 15 | 231728067 |
| 16 | 1077569125 |
| 17 | 4402483823 |
| 18 | 20583007623 |
| 19 | 85034398167 |
| 20 | 398951873741 |
| 21 | 1668087724597 |
| 22 | 7844558761569 |
| 23 | 33069790913997 |
| 24 | 155992820970213 |
| 25 | 662633252179911 |
| 26 | 3131081805336965 |
| 27 | 13392143350370781 |
[1,1,5,11,49,157,681,2371,10745,39323,179183, 689829,3166221,12438603,57683523,231728067, 1077569125,4402483823,20583007623,85034398167, 398951873741,1668087724597,7844558761569, 33069790913997,155992820970213,662633252179911, 3131081805336965,13392143350370781] |