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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 10 |
| 2 | 90 |
| 3 | 810 |
| 4 | 7245 |
| 5 | 64800 |
| 6 | 579600 |
| 7 | 5184000 |
| 8 | 46366380 |
| 9 | 414707040 |
| 10 | 3709193760 |
| 11 | 33175513440 |
| 12 | 296726124240 |
| 13 | 2653957198080 |
| 14 | 23737339710720 |
| 15 | 212309865780480 |
| 16 | 1898927161041600 |
| 17 | 16984252473131520 |
| 18 | 151909371770042880 |
[1,10,90,810,7245,64800,579600,5184000,46366380, 414707040,3709193760,33175513440,296726124240, 2653957198080,23737339710720,212309865780480, 1898927161041600,16984252473131520, 151909371770042880] |