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 | 2 |
| 3 | 4 |
| 4 | 10 |
| 5 | 27 |
| 6 | 79 |
| 7 | 247 |
| 8 | 816 |
| 9 | 2822 |
| 10 | 10158 |
| 11 | 37875 |
| 12 | 145695 |
| 13 | 576288 |
| 14 | 2337412 |
| 15 | 9698820 |
| 16 | 41089107 |
| 17 | 177424188 |
| 18 | 779699793 |
| 19 | 3482575169 |
| 20 | 15791709187 |
| 21 | 72621800171 |
| 22 | 338388714955 |
| 23 | 1596314968112 |
| 24 | 7618218238583 |
| 25 | 36756086159343 |
| 26 | 179176803145900 |
| 27 | 882002961543492 |