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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 11 |
| 3 | 222 |
| 4 | 6666 |
| 5 | 266664 |
| 6 | 13333320 |
| 7 | 799999920 |
| 8 | 55999999440 |
| 9 | 4479999995520 |
| 10 | 403199999959680 |
| 11 | 40319999999596800 |
| 12 | 4435199999995564800 |
| 13 | 532223999999946777600 |
| 14 | 69189119999999308108800 |
| 15 | 9686476799999990313523200 |
| 16 | 1452971519999999854702848000 |
| 17 | 232475443199999997675245568000 |
| 18 | 39520825343999999960479174656000 |
[1,11,222,6666,266664,13333320,799999920, 55999999440,4479999995520,403199999959680, 40319999999596800,4435199999995564800, 532223999999946777600,69189119999999308108800, 9686476799999990313523200, 1452971519999999854702848000, 232475443199999997675245568000, 39520825343999999960479174656000] |