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) |
|---|---|
| 2 | 0 |
| 3 | 3 |
| 4 | 106 |
| 5 | 17367 |
| 6 | 24601058 |
| 7 | 638520866656 |
| 8 | 169298265484672524 |
| 9 | 1292856744880357036357430 |