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| n | a(n) |
|---|---|
| 0 | 20 |
| 1 | 41 |
| 2 | 61 |
| 3 | 102 |
| 4 | 979 |
| 5 | 1081 |
| 6 | 2060 |
| 7 | 5201 |
| 8 | 210100 |
| 9 | 425401 |
| 10 | 635501 |
| 11 | 1060902 |
| 12 | 10183619 |
| 13 | 11244521 |
| 14 | 21428140 |
| 15 | 54100801 |
| 16 | 2185460180 |
| 17 | 4425021161 |
| 18 | 6610481341 |
| 19 | 11035502502 |
| 20 | 105930003859 |
| 21 | 116965506361 |
| 22 | 222895510220 |
| 23 | 562756526801 |
| 24 | 22733156582260 |
| 25 | 46029069691321 |
[20,41,61,102,979,1081,2060,5201,210100,425401, 635501,1060902,10183619,11244521,21428140, 54100801,2185460180,4425021161,6610481341, 11035502502,105930003859,116965506361, 222895510220,562756526801,22733156582260, 46029069691321] |