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 | 1 |
| 2 | 92 |
| 3 | 993 |
| 4 | 9994 |
| 5 | 99995 |
| 6 | 999996 |
| 7 | 9999997 |
| 8 | 99999998 |
| 9 | 999999999 |
| 10 | 9999999910 |
| 11 | 99999999911 |
| 12 | 999999999912 |
| 13 | 9999999999913 |
| 14 | 99999999999914 |
| 15 | 999999999999915 |
| 16 | 9999999999999916 |
| 17 | 99999999999999917 |
| 18 | 999999999999999918 |
| 19 | 9999999999999999919 |
| 20 | 99999999999999999920 |