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 | 5 |
| 2 | 15451 |
| 3 | 15551 |
| 4 | 1550551 |
| 5 | 154555451 |
| 6 | 155535551 |
| 7 | 355555553 |
| 8 | 35555155553 |
| 9 | 75555555557 |
| 10 | 1555550555551 |
| 11 | 152555555555251 |
| 12 | 10555555355555501 |
| 13 | 15505555555550551 |
| 14 | 35555555755555553 |
| 15 | 1555555055505555551 |
| 16 | 1555555551555555551 |
| 17 | 115555555555555555511 |