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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 9 |
| 2 | 99 |
| 3 | 1416 |
| 4 | 25650 |
| 5 | 569772 |
| 6 | 15099042 |
| 7 | 466865280 |
| 8 | 16545757617 |
| 9 | 662459717350 |
| 10 | 29611195466373 |
| 11 | 1463138718427008 |
| 12 | 79255793863426950 |
| 13 | 4673128560507694980 |
| 14 | 298096897542679853190 |
| 15 | 20462949699720864598464 |
| 16 | 1504570012129788012314910 |
| 17 | 118004419030927157257862025 |
[1,9,99,1416,25650,569772,15099042,466865280, 16545757617,662459717350,29611195466373, 1463138718427008,79255793863426950, 4673128560507694980,298096897542679853190, 20462949699720864598464,1504570012129788012314910, 118004419030927157257862025] |