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 | 15 |
| 3 | 115 |
| 4 | 1115 |
| 5 | 11115 |
| 6 | 111115 |
| 7 | 1111115 |
| 8 | 11111115 |
| 9 | 111111115 |
| 10 | 1111111115 |
| 11 | 11111111115 |
| 12 | 111111111115 |
| 13 | 1111111111115 |
| 14 | 11111111111115 |
| 15 | 111111111111115 |
| 16 | 1111111111111115 |
| 17 | 11111111111111115 |
| 18 | 111111111111111115 |
| 19 | 1111111111111111115 |
| 20 | 11111111111111111115 |
| 21 | 111111111111111111115 |