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) |
|---|---|
| 3 | 0 |
| 4 | 211 |
| 5 | 3325 |
| 6 | 555551 |
| 7 | 77777775 |
| 8 | 20000000211 |
| 9 | 30000003325 |
| 10 | 50000555551 |
| 11 | 70077777775 |
| 12 | 100000000211 |
| 13 | 100000003325 |
| 14 | 100000555551 |
| 15 | 100077777775 |