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| n | a(n) |
|---|---|
| 1 | 21 |
| 2 | 129 |
| 3 | 1003 |
| 4 | 10681 |
| 5 | 101829 |
| 6 | 1020831 |
| 7 | 10251129 |
| 8 | 100780743 |
| 9 | 1051460221 |
| 10 | 10153541853 |
| 11 | 103257526729 |
| 12 | 1483112006019 |
[21,129,1003,10681,101829,1020831,10251129, 100780743,1051460221,10153541853,103257526729, 1483112006019] |