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 | 23 |
| 3 | 223 |
| 4 | 2003 |
| 5 | 20021 |
| 6 | 200003 |
| 7 | 2000003 |
| 8 | 20000003 |
| 9 | 200000069 |
| 10 | 2000000063 |
| 11 | 20000000089 |
| 12 | 200000000041 |
| 13 | 2000000000003 |
| 14 | 20000000000021 |
| 15 | 200000000000027 |
| 16 | 2000000000000021 |
| 17 | 20000000000000003 |
| 18 | 200000000000000003 |
| 19 | 2000000000000000221 |
| 20 | 20000000000000000401 |