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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 11 |
| 3 | 124 |
| 4 | 1397 |
| 5 | 15739 |
| 6 | 177320 |
| 7 | 1997737 |
| 8 | 22507067 |
| 9 | 253570948 |
| 10 | 2856801629 |
| 11 | 32185530763 |
| 12 | 362611243280 |
| 13 | 4085280268369 |
| 14 | 46025916681899 |
| 15 | 518540924305996 |
| 16 | 5842027917411653 |
| 17 | 65817929864446171 |
| 18 | 741523312261142840 |
| 19 | 8354210224465909753 |
[0,1,11,124,1397,15739,177320,1997737,22507067, 253570948,2856801629,32185530763,362611243280, 4085280268369,46025916681899,518540924305996, 5842027917411653,65817929864446171, 741523312261142840,8354210224465909753] |