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| n | a(n) |
|---|---|
| 1 | 5 |
| 2 | 17 |
| 3 | 53 |
| 4 | 3545 |
| 5 | 8369 |
| 6 | 823633 |
| 7 | 499025 |
| 8 | 669937733 |
| 9 | 722651597 |
| 10 | 35034942905 |
| 11 | 173113684537 |
| 12 | 1860490554949 |
| 13 | 21906189996125 |
| 14 | 2320160748906089 |
| 15 | 1347255903779016125 |
| 16 | 49174444344033218405 |
| 17 | 436006592777392918253129 |
| 18 | 31471103940926430492910889 |
[5,17,53,3545,8369,823633,499025,669937733, 722651597,35034942905,173113684537,1860490554949, 21906189996125,2320160748906089, 1347255903779016125,49174444344033218405, 436006592777392918253129, 31471103940926430492910889] |