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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 10 |
| 3 | 40 |
| 4 | 184 |
| 5 | 824 |
| 6 | 3864 |
| 7 | 17984 |
| 8 | 85184 |
| 9 | 403712 |
| 10 | 1930496 |
| 11 | 9244544 |
| 12 | 44489600 |
| 13 | 214497152 |
| 14 | 1037518208 |
| 15 | 5026380800 |
| 16 | 24405484544 |
| 17 | 118666545152 |
| 18 | 577960470528 |
| 19 | 2818255560704 |
| 20 | 13760256729088 |
| 21 | 67253185175552 |
| 22 | 329044599758848 |
| 23 | 1611283311788032 |
| 24 | 7897046179938304 |
| 25 | 38733053764009984 |
| 26 | 190114821489393664 |
[1,2,10,40,184,824,3864,17984,85184,403712, 1930496,9244544,44489600,214497152,1037518208, 5026380800,24405484544,118666545152,577960470528, 2818255560704,13760256729088,67253185175552, 329044599758848,1611283311788032,7897046179938304, 38733053764009984,190114821489393664] |