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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 8 |
| 4 | 34 |
| 5 | 170 |
| 6 | 1021 |
| 7 | 7152 |
| 8 | 57216 |
| 9 | 514951 |
| 10 | 5149512 |
| 11 | 56644635 |
| 12 | 679735626 |
| 13 | 8836563141 |
| 14 | 123711883983 |
| 15 | 1855678259755 |
| 16 | 29690852156095 |
| 17 | 504744486653631 |
| 18 | 9085400759765361 |
| 19 | 172622614435541861 |
| 20 | 3452452288710837226 |
[1,2,8,34,170,1021,7152,57216,514951,5149512, 56644635,679735626,8836563141,123711883983, 1855678259755,29690852156095,504744486653631, 9085400759765361,172622614435541861, 3452452288710837226] |