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 | 1 |
| 2 | 4 |
| 3 | 7 |
| 4 | 6 |
| 5 | 5 |
| 6 | 6 |
| 7 | 3 |
| 8 | 6 |
| 9 | 9 |
| 10 | 10000000000 |
| 11 | 115502205511 |
| 12 | 1440046600466 |
| 13 | 19225142754633 |
| 14 | 166668888866666 |
| 15 | 1555555555555555 |
| 16 | 16000880008800066 |
| 17 | 194006440028800877 |
| 18 | 1422046880284402844 |
| 19 | 11116222228888849999 |
| 20 | 600000000000000000000 |
| 21 | 2600042000840006800021 |