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 | 4 |
| 2 | 6 |
| 3 | 9 |
| 4 | 22 |
| 5 | 33 |
| 6 | 55 |
| 7 | 77 |
| 8 | 111 |
| 9 | 1111 |
| 10 | 11111 |
| 11 | 1111111 |
| 12 | 11111111111 |
| 13 | 11111111111111111 |
| 14 | 2222222222222222222 |
| 15 | 3333333333333333333 |
| 16 | 5555555555555555555 |
| 17 | 7777777777777777777 |
| 18 | 22222222222222222222222 |
| 19 | 33333333333333333333333 |
| 20 | 55555555555555555555555 |