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| n | a(n) |
|---|---|
| 1 | 20 |
| 2 | 400 |
| 3 | 5172 |
| 4 | 65297 |
| 5 | 862652 |
| 6 | 11451149 |
| 7 | 151788273 |
| 8 | 2010430729 |
| 9 | 26638642226 |
| 10 | 353018801580 |
| 11 | 4678246752829 |
| 12 | 61995665582140 |
| 13 | 821565095555503 |
| 14 | 10887399620742611 |
| 15 | 144280214103179733 |
| 16 | 1912006322548221320 |
[20,400,5172,65297,862652,11451149,151788273, 2010430729,26638642226,353018801580,4678246752829, 61995665582140,821565095555503,10887399620742611, 144280214103179733,1912006322548221320] |