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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 66 |
| 3 | 423 |
| 4 | 9768 |
| 5 | 251025 |
| 6 | 1253142 |
| 7 | 7123907 |
| 8 | 169108896 |
| 9 | 903996009 |
| 10 | 10004500100 |
| 11 | 110067122011 |
| 12 | 2520202950144 |
| 13 | 13001275950013 |
| 14 | 280009919140028 |
| 15 | 7500003630000075 |
| 16 | 33760012606001792 |
| 17 | 170000242046000017 |
[1,66,423,9768,251025,1253142,7123907,169108896, 903996009,10004500100,110067122011,2520202950144, 13001275950013,280009919140028,7500003630000075, 33760012606001792,170000242046000017] |