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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 8 |
| 4 | 32 |
| 5 | 160 |
| 6 | 963 |
| 7 | 6746 |
| 8 | 53974 |
| 9 | 485771 |
| 10 | 4857717 |
| 11 | 53434892 |
| 12 | 641218712 |
| 13 | 8335843266 |
| 14 | 116701805732 |
| 15 | 1750527085987 |
| 16 | 28008433375798 |
| 17 | 476143367388568 |
| 18 | 8570580612994224 |
| 19 | 162841031646890261 |
| 20 | 3256820632937805228 |
[1,2,8,32,160,963,6746,53974,485771,4857717, 53434892,641218712,8335843266,116701805732, 1750527085987,28008433375798,476143367388568, 8570580612994224,162841031646890261, 3256820632937805228] |