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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 10 |
| 2 | 201 |
| 3 | 2020 |
| 4 | 40601 |
| 5 | 408030 |
| 6 | 8201201 |
| 7 | 82420040 |
| 8 | 1656602001 |
| 9 | 16648440050 |
| 10 | 334625403001 |
| 11 | 3362902470060 |
| 12 | 67592674804201 |
| 13 | 679289650512070 |
| 14 | 13653385685045601 |
| 15 | 137213146500968080 |
| 16 | 2757916315704407201 |
| 17 | 27716376303545040090 |
| 18 | 557085442386605209001 |
[1,10,201,2020,40601,408030,8201201,82420040, 1656602001,16648440050,334625403001,3362902470060, 67592674804201,679289650512070,13653385685045601, 137213146500968080,2757916315704407201, 27716376303545040090,557085442386605209001] |