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| n | a(n) |
|---|---|
| 1 | 5 |
| 2 | 9 |
| 3 | 53 |
| 4 | 137 |
| 5 | 853 |
| 6 | 2953 |
| 7 | 17333 |
| 8 | 71721 |
| 9 | 394325 |
| 10 | 1791209 |
| 11 | 9435253 |
| 12 | 44924617 |
| 13 | 230950613 |
| 14 | 1126125513 |
| 15 | 5713545653 |
| 16 | 28200027881 |
| 17 | 142082597845 |
| 18 | 705663892009 |
| 19 | 3542422689653 |
| 20 | 17650591452297 |
| 21 | 88436516562773 |
| 22 | 441384307595273 |
[5,9,53,137,853,2953,17333,71721,394325,1791209, 9435253,44924617,230950613,1126125513,5713545653, 28200027881,142082597845,705663892009, 3542422689653,17650591452297,88436516562773, 441384307595273] |