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 | 1000 |
| 2 | 1100 |
| 3 | 1110 |
| 4 | 1111 |
| 5 | 10100 |
| 6 | 11112 |
| 7 | 11120 |
| 8 | 11121 |
| 9 | 11122 |
| 10 | 11200 |
| 11 | 11210 |
| 12 | 11211 |
| 13 | 11220 |
| 14 | 11221 |
| 15 | 11222 |
| 16 | 12000 |
| 17 | 12100 |
| 18 | 12110 |
| 19 | 12111 |
| 20 | 12200 |
| 21 | 12210 |
| 22 | 12211 |
| 23 | 12220 |
| 24 | 12221 |
| 25 | 12222 |
| 26 | 20000 |
| 27 | 21000 |
| 28 | 21100 |
| 29 | 21110 |
| 30 | 21111 |
| 31 | 22000 |
| 32 | 22100 |
| 33 | 22110 |
| 34 | 22111 |
| 35 | 22200 |
| 36 | 22210 |
| 37 | 22211 |
| 38 | 22220 |
| 39 | 22221 |
| 40 | 22222 |