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| n | a(n) |
|---|---|
| 1 | 6 |
| 2 | 34 |
| 3 | 232 |
| 4 | 1986 |
| 5 | 20040 |
| 6 | 220235 |
| 7 | 2499080 |
| 8 | 28501471 |
| 9 | 323067002 |
| 10 | 3626695952 |
| 11 | 40306404192 |
| 12 | 443852375808 |
| 13 | 4848323701804 |
| 14 | 52590398731297 |
| 15 | 567018802063680 |
| 16 | 6081537709403509 |
| 17 | 64929807220896558 |
| 18 | 690446673537426382 |
[6,34,232,1986,20040,220235,2499080,28501471, 323067002,3626695952,40306404192,443852375808, 4848323701804,52590398731297,567018802063680, 6081537709403509,64929807220896558, 690446673537426382] |