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 | 5 |
| 3 | 14 |
| 4 | 93 |
| 5 | 602 |
| 6 | 5847 |
| 7 | 66289 |
| 8 | 937696 |
| 9 | 15575285 |
| 10 | 301360805 |
| 11 | 6663874305 |
| 12 | 166516898890 |
| 13 | 4654082023569 |
| 14 | 144301649717895 |
| 15 | 4928171085359360 |
| 16 | 184252862642720722 |
| 17 | 7501009857590958129 |
| 18 | 330928677041195111955 |
| 19 | 15754816518916261088582 |
| 20 | 806306082299053607173143 |