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| n | a(n) |
|---|---|
| 1 | 55 |
| 2 | 187 |
| 3 | 1271 |
| 4 | 3953 |
| 5 | 13843 |
| 6 | 34189 |
| 7 | 78391 |
| 8 | 129551 |
| 9 | 307961 |
| 10 | 351613 |
| 11 | 616081 |
| 12 | 753343 |
| 13 | 1155481 |
| 14 | 1350163 |
| 15 | 1461617 |
| 16 | 2073551 |
| 17 | 2282977 |
| 18 | 2999743 |
| 19 | 3367081 |
| 20 | 4293103 |
| 21 | 5503691 |
| 22 | 8427373 |
| 23 | 9060019 |
| 24 | 10751441 |
| 25 | 14039813 |
| 26 | 17164349 |
| 27 | 19439137 |
| 28 | 20775283 |
| 29 | 22781333 |
[55,187,1271,3953,13843,34189,78391,129551,307961, 351613,616081,753343,1155481,1350163,1461617, 2073551,2282977,2999743,3367081,4293103,5503691, 8427373,9060019,10751441,14039813,17164349, 19439137,20775283,22781333] |