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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 3 |
| 3 | 8 |
| 4 | 34 |
| 5 | 89 |
| 6 | 987 |
| 7 | 196418 |
| 8 | 2178309 |
| 9 | 5702887 |
| 10 | 24157817 |
| 11 | 165580141 |
| 12 | 433494437 |
| 13 | 4807526976 |
| 14 | 12586269025 |
| 15 | 32951280099 |
| 16 | 86267571272 |
| 17 | 365435296162 |
| 18 | 956722026041 |
| 19 | 4052739537881 |
| 20 | 8944394323791464 |
| 21 | 23416728348467685 |
[2,3,8,34,89,987,196418,2178309,5702887,24157817, 165580141,433494437,4807526976,12586269025, 32951280099,86267571272,365435296162,956722026041, 4052739537881,8944394323791464,23416728348467685] |