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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 10 |
| 2 | 55 |
| 3 | 340 |
| 4 | 2530 |
| 5 | 20008 |
| 6 | 166870 |
| 7 | 1428580 |
| 8 | 12501280 |
| 9 | 111111340 |
| 10 | 1000010044 |
| 11 | 9090909100 |
| 12 | 83333418520 |
| 13 | 769230769240 |
| 14 | 7142857857190 |
| 15 | 66666666680272 |
| 16 | 625000006251280 |
| 17 | 5882352941176480 |
| 18 | 55555555611222370 |
| 19 | 526315789473684220 |
[1,10,55,340,2530,20008,166870,1428580,12501280, 111111340,1000010044,9090909100,83333418520, 769230769240,7142857857190,66666666680272, 625000006251280,5882352941176480, 55555555611222370,526315789473684220] |