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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 10 |
| 3 | 62 |
| 4 | 448 |
| 5 | 3464 |
| 6 | 28111 |
| 7 | 236022 |
| 8 | 2033145 |
| 9 | 17867442 |
| 10 | 159558635 |
| 11 | 1443747386 |
| 12 | 13207922431 |
| 13 | 121962046864 |
| 14 | 1135246916024 |
| 15 | 10640772522150 |
| 16 | 100346005711723 |
| 17 | 951400275042466 |
| 18 | 9063703952844960 |
| 19 | 86718277215053218 |
| 20 | 832901296331740527 |
[1,2,10,62,448,3464,28111,236022,2033145,17867442, 159558635,1443747386,13207922431,121962046864, 1135246916024,10640772522150,100346005711723, 951400275042466,9063703952844960, 86718277215053218,832901296331740527] |