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 | 0 |
| 2 | 1 |
| 3 | 5 |
| 4 | 87 |
| 5 | 6398 |
| 6 | 7745253 |
| 7 | 2414573042063 |
| 8 | 56130437190053518791691 |
| 9 | 286386577668298410118121281898931424413687 |