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| n | a(n) |
|---|---|
| 1 | 23 |
| 2 | 43 |
| 3 | 67 |
| 4 | 89 |
| 5 | 109 |
| 6 | 1213 |
| 7 | 2221 |
| 8 | 2423 |
| 9 | 3433 |
| 10 | 3637 |
| 11 | 4241 |
| 12 | 4243 |
| 13 | 5051 |
| 14 | 5657 |
| 15 | 5857 |
| 16 | 6263 |
| 17 | 6869 |
| 18 | 7069 |
| 19 | 7877 |
| 20 | 7879 |
| 21 | 8081 |
| 22 | 8887 |
| 23 | 9091 |
| 24 | 9293 |
| 25 | 9697 |
| 26 | 10099 |
| 27 | 102101 |
| 28 | 102103 |
| 29 | 108107 |
| 30 | 108109 |
| 31 | 112111 |
| 32 | 114113 |
| 33 | 120121 |
| 34 | 124123 |
| 35 | 126127 |
| 36 | 138139 |
| 37 | 148147 |
| 38 | 150151 |
[23,43,67,89,109,1213,2221,2423,3433,3637,4241, 4243,5051,5657,5857,6263,6869,7069,7877,7879,8081, 8887,9091,9293,9697,10099,102101,102103,108107, 108109,112111,114113,120121,124123,126127,138139, 148147,150151] |