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 | 1 |
| 1 | 414 |
| 2 | 44144 |
| 3 | 4441444 |
| 4 | 444414444 |
| 5 | 44444144444 |
| 6 | 4444441444444 |
| 7 | 444444414444444 |
| 8 | 44444444144444444 |
| 9 | 4444444441444444444 |
| 10 | 444444444414444444444 |
| 11 | 44444444444144444444444 |
| 12 | 4444444444441444444444444 |
| 13 | 444444444444414444444444444 |
| 14 | 44444444444444144444444444444 |
| 15 | 4444444444444441444444444444444 |