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 | 2 |
| 2 | 7 |
| 3 | 114 |
| 4 | 9602 |
| 5 | 3962940 |
| 6 | 7516789560 |
| 7 | 62622777447552 |
| 8 | 2221417812173570640 |