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) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 6 |
| 5 | 30 |
| 6 | 1202 |
| 7 | 3207410 |
| 8 | 7925688042914 |
| 9 | 251265071655132399283480418 |
| 10 | 79278147718866210084428917149363438284974325840642 |