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 | 1 |
| 3 | 2 |
| 4 | 6 |
| 5 | 26 |
| 6 | 154 |
| 7 | 1188 |
| 8 | 11474 |
| 9 | 134432 |
| 10 | 1863168 |
| 11 | 29936846 |
| 12 | 548625820 |
| 13 | 11315025894 |
| 14 | 259733293774 |
| 15 | 6574304470320 |
| 16 | 182050022755386 |
| 17 | 5477819548007438 |
| 18 | 178054691097463354 |
| 19 | 6220193033111607018 |