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| n | a(n) |
|---|---|
| 1 | 42 |
| 2 | 208 |
| 3 | 1048 |
| 4 | 5328 |
| 5 | 27168 |
| 6 | 138720 |
| 7 | 708640 |
| 8 | 3620768 |
| 9 | 18501536 |
| 10 | 94542752 |
| 11 | 483118496 |
| 12 | 2468772768 |
| 13 | 12615641504 |
| 14 | 64467060640 |
| 15 | 329432556960 |
| 16 | 1683430581152 |
| 17 | 8602485031328 |
| 18 | 43959490084768 |
| 19 | 224637040795040 |
| 20 | 1147915959163808 |
[42,208,1048,5328,27168,138720,708640,3620768, 18501536,94542752,483118496,2468772768, 12615641504,64467060640,329432556960, 1683430581152,8602485031328,43959490084768, 224637040795040,1147915959163808] |