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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 121 |
| 4 | 10201 |
| 5 | 12321 |
| 6 | 1002001 |
| 7 | 1032301 |
| 8 | 1223221 |
| 9 | 100020001 |
| 10 | 102030201 |
| 11 | 103101301 |
| 12 | 120202021 |
| 13 | 10000200001 |
| 14 | 10033233001 |
| 15 | 1000002000001 |
| 16 | 1002003002001 |
| 17 | 1003010103001 |
| 18 | 1021320231201 |
| 19 | 1211130311121 |
| 20 | 1212110112121 |
| 21 | 1213332333121 |
| 22 | 100000020000001 |
| 23 | 100033323330001 |
| 24 | 100331000133001 |
[0,1,121,10201,12321,1002001,1032301,1223221, 100020001,102030201,103101301,120202021, 10000200001,10033233001,1000002000001, 1002003002001,1003010103001,1021320231201, 1211130311121,1212110112121,1213332333121, 100000020000001,100033323330001,100331000133001] |