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) |
|---|---|
| 2 | 19 |
| 3 | 211 |
| 4 | 2221 |
| 5 | 22193 |
| 6 | 222199 |
| 7 | 2222219 |
| 8 | 22222199 |
| 9 | 222222193 |
| 10 | 2222222137 |
| 11 | 22222222189 |
| 12 | 222222222169 |
| 13 | 2222222222197 |
| 14 | 22222222222201 |
| 15 | 222222222222151 |
| 16 | 2222222222222203 |
| 17 | 22222222222222153 |
| 18 | 222222222222222221 |
| 19 | 2222222222222222177 |
| 20 | 22222222222222222169 |
| 21 | 222222222222222222149 |
| 22 | 2222222222222222222161 |