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 | 4 |
| 2 | 100 |
| 3 | 1100100 |
| 4 | 100001100100101000100 |
| 5 | 1010110101111001011010001101011011001100110110011001100101110100100 |