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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 34 |
| 3 | 1156 |
| 4 | 20570 |
| 5 | 366025 |
| 6 | 7320500 |
| 7 | 146410000 |
| 8 | 2898918000 |
| 9 | 57398576400 |
| 10 | 1136955639600 |
| 11 | 22520909184400 |
| 12 | 446088564737200 |
| 13 | 8836011280003600 |
| 14 | 175021631355863600 |
| 15 | 3466787272192723600 |
| 16 | 68669304273355566000 |
[1,34,1156,20570,366025,7320500,146410000, 2898918000,57398576400,1136955639600, 22520909184400,446088564737200,8836011280003600, 175021631355863600,3466787272192723600, 68669304273355566000] |