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) |
|---|---|
| 10 | 11 |
| 11 | 22 |
| 12 | 33 |
| 13 | 44 |
| 14 | 55 |
| 15 | 66 |
| 16 | 77 |
| 17 | 88 |
| 18 | 99 |
| 19 | 132 |
| 20 | 264 |
| 21 | 396 |