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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 17 |
| 3 | 139 |
| 4 | 1114 |
| 5 | 8913 |
| 6 | 71307 |
| 7 | 570458 |
| 8 | 4563665 |
| 9 | 36509323 |
| 10 | 292074586 |
| 11 | 2336596689 |
| 12 | 18692773515 |
| 13 | 149542188122 |
| 14 | 1196337504977 |
| 15 | 9570700039819 |
| 16 | 76565600318554 |
| 17 | 612524802548433 |
| 18 | 4900198420387467 |
[2,17,139,1114,8913,71307,570458,4563665,36509323, 292074586,2336596689,18692773515,149542188122, 1196337504977,9570700039819,76565600318554, 612524802548433,4900198420387467] |