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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 4 |
| 3 | 10 |
| 4 | 34 |
| 5 | 162 |
| 6 | 1090 |
| 7 | 10370 |
| 8 | 139522 |
| 9 | 2654722 |
| 10 | 71435266 |
| 11 | 2718435330 |
| 12 | 146299424770 |
| 13 | 11134711111682 |
| 14 | 1198484887715842 |
| 15 | 182431106853797890 |
| 16 | 39271952800672710658 |
| 17 | 11955805018770498519042 |
| 18 | 5147453397489773531365378 |
[1,2,4,10,34,162,1090,10370,139522,2654722, 71435266,2718435330,146299424770,11134711111682, 1198484887715842,182431106853797890, 39271952800672710658,11955805018770498519042, 5147453397489773531365378] |