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 | 0 |
| 1 | 1 |
| 2 | 1 |
| 3 | 4 |
| 4 | 9 |
| 5 | 25 |
| 6 | 64 |
| 7 | 403 |
| 8 | 252 |
| 9 | 1462 |
| 10 | 3025 |
| 11 | 8722 |
| 12 | 63504 |
| 13 | 77356 |
| 14 | 291421 |
| 15 | 9760 |
| 16 | 778743 |
| 17 | 12697747 |
| 18 | 12537568 |
| 19 | 7584334 |
| 20 | 38398140 |
| 21 | 710406346 |
| 22 | 208476181 |
| 23 | 2168819074 |
| 24 | 4004525952 |
| 25 | 3905576425 |
| 26 | 47722137553 |
| 27 | 160019976838 |
| 28 | 37728297243 |
| 29 | 474332543035 |
| 30 | 33479625520 |