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 | 10 |
| 2 | 1010 |
| 3 | 1210 |
| 4 | 101010 |
| 5 | 101210 |
| 6 | 121010 |
| 7 | 121210 |
| 8 | 123210 |
| 9 | 10101010 |
| 10 | 10101210 |
| 11 | 10121010 |
| 12 | 10121210 |
| 13 | 10123210 |
| 14 | 12101010 |
| 15 | 12101210 |
| 16 | 12121010 |
| 17 | 12121210 |
| 18 | 12123210 |
| 19 | 12321010 |
| 20 | 12321210 |
| 21 | 12323210 |
| 22 | 12343210 |
| 23 | 1010101010 |
| 24 | 1010101210 |