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| n | a(n) |
|---|---|
| 1 | 31 |
| 2 | 71 |
| 3 | 251 |
| 4 | 271 |
| 5 | 331 |
| 6 | 521 |
| 7 | 571 |
| 8 | 751 |
| 9 | 4231 |
| 10 | 4271 |
| 11 | 4721 |
| 12 | 4751 |
| 13 | 6221 |
| 14 | 6271 |
| 15 | 6521 |
| 16 | 6551 |
| 17 | 6571 |
| 18 | 8221 |
| 19 | 8231 |
| 20 | 8521 |
| 21 | 8731 |
| 22 | 9221 |
| 23 | 9371 |
| 24 | 9521 |
| 25 | 9551 |
| 26 | 9721 |
| 27 | 20231 |
| 28 | 20521 |
| 29 | 20551 |
| 30 | 20731 |
| 31 | 20771 |
| 32 | 24251 |
| 33 | 24371 |
| 34 | 24551 |
| 35 | 24571 |
| 36 | 26251 |
| 37 | 26321 |
| 38 | 26371 |
| 39 | 26731 |
| 40 | 28351 |
[31,71,251,271,331,521,571,751,4231,4271,4721, 4751,6221,6271,6521,6551,6571,8221,8231,8521,8731, 9221,9371,9521,9551,9721,20231,20521,20551,20731, 20771,24251,24371,24551,24571,26251,26321,26371, 26731,28351] |