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 | 2 |
| 2 | 3 |
| 3 | 5 |
| 4 | 7 |
| 5 | 29 |
| 6 | 49 |
| 7 | 89 |
| 8 | 199 |
| 9 | 599 |
| 10 | 2999 |
| 11 | 4999 |
| 12 | 19999 |
| 13 | 59999 |
| 14 | 79999 |
| 15 | 299999 |
| 16 | 899999 |
| 17 | 5999999 |
| 18 | 7999999 |
| 19 | 49999999 |
| 20 | 89999999 |
| 21 | 199999999 |
| 22 | 799999999 |
| 23 | 2999999999 |
| 24 | 8999999999 |
| 25 | 79999999999 |
| 26 | 299999999999 |
| 27 | 499999999999 |
| 28 | 899999999999 |