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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 5 |
| 3 | 7 |
| 4 | 11 |
| 5 | 13 |
| 6 | 17 |
| 7 | 19 |
| 8 | 331 |
| 9 | 661 |
| 10 | 881 |
| 11 | 991 |
| 12 | 20201 |
| 13 | 60601 |
| 14 | 90901 |
| 15 | 2002001 |
| 16 | 5005001 |
| 17 | 300030001 |
| 18 | 600060001 |
| 19 | 50000500001 |
| 20 | 2000002000001 |
| 21 | 8000008000001 |
| 22 | 9000009000001 |
| 23 | 3000000003000000001 |
| 24 | 200000000020000000001 |
| 25 | 80000000000800000000001 |
[3,5,7,11,13,17,19,331,661,881,991,20201,60601, 90901,2002001,5005001,300030001,600060001, 50000500001,2000002000001,8000008000001, 9000009000001,3000000003000000001, 200000000020000000001,80000000000800000000001] |