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| n | a(n) |
|---|---|
| 1 | 7 |
| 2 | 18 |
| 3 | 286 |
| 4 | 3010 |
| 5 | 32890 |
| 6 | 769230 |
| 7 | 3333330 |
| 8 | 159189030 |
| 9 | 16015883940 |
| 10 | 477463360374 |
| 11 | 21643407275490 |
| 12 | 1148540321999070 |
| 13 | 18489352726664820 |
| 14 | 4561561662153109614 |
| 15 | 71000485538666794110 |
| 16 | 14440652550858108745170 |
| 17 | 927869754030522488795610 |
[7,18,286,3010,32890,769230,3333330,159189030, 16015883940,477463360374,21643407275490, 1148540321999070,18489352726664820, 4561561662153109614,71000485538666794110, 14440652550858108745170,927869754030522488795610] |