This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
| n | a(n) |
|---|---|
| 1 | 313 |
| 2 | 353 |
| 3 | 373 |
| 4 | 383 |
| 5 | 727 |
| 6 | 757 |
| 7 | 787 |
| 8 | 797 |
| 9 | 11311 |
| 10 | 11411 |
| 11 | 1311131 |
| 12 | 1317131 |
| 13 | 1513151 |
| 14 | 1917191 |
| 15 | 9196919 |
| 16 | 9199919 |
| 17 | 10301110301 |
| 18 | 10301910301 |
| 19 | 10501210501 |
| 20 | 10501910501 |
| 21 | 10601110601 |
| 22 | 12421212421 |
| 23 | 12421812421 |
| 24 | 12721612721 |
| 25 | 13331113331 |
| 26 | 13331713331 |
| 27 | 13831913831 |
| 28 | 13931413931 |