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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 11 |
| 3 | 82 |
| 4 | 612 |
| 5 | 4568 |
| 6 | 34096 |
| 7 | 254496 |
| 8 | 1899584 |
| 9 | 14178688 |
| 10 | 105831168 |
| 11 | 789934592 |
| 12 | 5896152064 |
| 13 | 44009478144 |
| 14 | 328491216896 |
| 15 | 2451891822592 |
| 16 | 18301169713152 |
| 17 | 136601790414848 |
| 18 | 1019609644466176 |
| 19 | 7610469994070016 |
| 20 | 56805321374695424 |
[2,11,82,612,4568,34096,254496,1899584,14178688, 105831168,789934592,5896152064,44009478144, 328491216896,2451891822592,18301169713152, 136601790414848,1019609644466176,7610469994070016, 56805321374695424] |