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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 3 |
| 3 | 11 |
| 4 | 37 |
| 5 | 109 |
| 6 | 349 |
| 7 | 1009 |
| 8 | 2801 |
| 9 | 7759 |
| 10 | 21157 |
| 11 | 56611 |
| 12 | 150107 |
| 13 | 394817 |
| 14 | 1031141 |
| 15 | 2676301 |
| 16 | 6908743 |
| 17 | 17756213 |
| 18 | 45456347 |
| 19 | 115973411 |
| 20 | 294965017 |
| 21 | 748174379 |
| 22 | 1893049583 |
[2,3,11,37,109,349,1009,2801,7759,21157,56611, 150107,394817,1031141,2676301,6908743,17756213, 45456347,115973411,294965017,748174379,1893049583] |