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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 14 |
| 3 | 107 |
| 4 | 844 |
| 5 | 6757 |
| 6 | 54522 |
| 7 | 441863 |
| 8 | 3589880 |
| 9 | 29206025 |
| 10 | 237780982 |
| 11 | 1936486411 |
| 12 | 15771410420 |
| 13 | 128431734797 |
| 14 | 1045618229234 |
| 15 | 8510270668815 |
| 16 | 69241255165936 |
| 17 | 563154350637073 |
| 18 | 4578526894227438 |
| 19 | 37209886138826771 |
| 20 | 302291556342169580 |
[2,14,107,844,6757,54522,441863,3589880,29206025, 237780982,1936486411,15771410420,128431734797, 1045618229234,8510270668815,69241255165936, 563154350637073,4578526894227438, 37209886138826771,302291556342169580] |