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| n | a(n) |
|---|---|
| 1 | 31 |
| 2 | 421 |
| 3 | 521 |
| 4 | 631 |
| 5 | 9421 |
| 6 | 14731 |
| 7 | 15731 |
| 8 | 189421 |
| 9 | 36189421 |
| 10 | 39199421 |
| 11 | 492412631 |
| 12 | 542713631 |
| 13 | 603015731 |
| 14 | 7236189421 |
| 15 | 7537189421 |
| 16 | 97482412631 |
| 17 | 99492412631 |
| 18 | 102512512631 |
| 19 | 107532613631 |
| 20 | 114572814731 |
| 21 | 1477336189421 |
| 22 | 18291452211521 |
| 23 | 18693462311521 |
| 24 | 19396482412631 |
[31,421,521,631,9421,14731,15731,189421,36189421, 39199421,492412631,542713631,603015731,7236189421, 7537189421,97482412631,99492412631,102512512631, 107532613631,114572814731,1477336189421, 18291452211521,18693462311521,19396482412631] |