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 | 3 |
| 2 | 12 |
| 3 | 21 |
| 4 | 30 |
| 5 | 111 |
| 6 | 120 |
| 7 | 201 |
| 8 | 210 |
| 9 | 1020 |
| 10 | 1101 |
| 11 | 1110 |
| 12 | 2010 |
| 13 | 10020 |
| 14 | 10101 |
| 15 | 10110 |
| 16 | 11010 |
| 17 | 20100 |
| 18 | 100020 |
| 19 | 100101 |
| 20 | 100110 |
| 21 | 101010 |
| 22 | 110100 |
| 23 | 200100 |
| 24 | 300000 |
| 25 | 1000101 |
| 26 | 1000110 |
| 27 | 1001010 |
| 28 | 1010100 |
| 29 | 1100100 |
| 30 | 1200000 |
| 31 | 2000010 |
| 32 | 2100000 |
| 33 | 10000020 |
| 34 | 10000101 |