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 | 18 |
| 5 | 56 |
| 6 | 272 |
| 7 | 1000 |
| 8 | 6080 |
| 9 | 33644 |
| 10 | 214024 |
| 11 | 1363836 |
| 12 | 10877964 |
| 13 | 75783376 |
| 14 | 648644300 |
| 15 | 5765475224 |
| 16 | 49406530846 |
| 17 | 431491536076 |