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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 2 |
| 3 | 11 |
| 4 | 76 |
| 5 | 685 |
| 6 | 7534 |
| 7 | 97943 |
| 8 | 1469144 |
| 9 | 24975449 |
| 10 | 474533530 |
| 11 | 9965204131 |
| 12 | 229199695012 |
| 13 | 5729992375301 |
| 14 | 154709794133126 |
| 15 | 4486584029860655 |
| 16 | 139084104925680304 |
| 17 | 4589775462547450033 |
| 18 | 160642141189160751154 |
| 19 | 5943759223998947792699 |
| 20 | 231806609735958963915260 |
[0,1,2,11,76,685,7534,97943,1469144,24975449, 474533530,9965204131,229199695012,5729992375301, 154709794133126,4486584029860655, 139084104925680304,4589775462547450033, 160642141189160751154,5943759223998947792699, 231806609735958963915260] |