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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 12 |
| 2 | 117 |
| 3 | 1080 |
| 4 | 9801 |
| 5 | 88452 |
| 6 | 796797 |
| 7 | 7173360 |
| 8 | 64566801 |
| 9 | 581120892 |
| 10 | 5230147077 |
| 11 | 47071500840 |
| 12 | 423644039001 |
| 13 | 3812797945332 |
| 14 | 34315186290957 |
| 15 | 308836690967520 |
| 16 | 2779530261754401 |
| 17 | 25015772484929772 |
| 18 | 225141952751788437 |
[1,12,117,1080,9801,88452,796797,7173360,64566801, 581120892,5230147077,47071500840,423644039001, 3812797945332,34315186290957,308836690967520, 2779530261754401,25015772484929772, 225141952751788437] |