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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 11 |
| 4 | 111 |
| 5 | 616 |
| 6 | 4448 |
| 7 | 23614 |
| 8 | 100943 |
| 9 | 430134 |
| 10 | 1529622 |
| 11 | 5273780 |
| 12 | 18181274 |
[0,1,11,111,616,4448,23614,100943,430134,1529622, 5273780,18181274] |