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) |
|---|---|
| 0 | 12 |
| 1 | 111 |
| 2 | 1101 |
| 3 | 11001 |
| 4 | 110001 |
| 5 | 1100001 |
| 6 | 11000001 |
| 7 | 110000001 |
| 8 | 1100000001 |
| 9 | 11000000001 |
| 10 | 110000000001 |
| 11 | 1100000000001 |
| 12 | 11000000000001 |
| 13 | 110000000000001 |
| 14 | 1100000000000001 |
| 15 | 11000000000000001 |
| 16 | 110000000000000001 |
| 17 | 1100000000000000001 |
| 18 | 11000000000000000001 |
| 19 | 110000000000000000001 |