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 | 3 |
| 3 | 30 |
| 4 | 1912 |
| 5 | 18662590 |
| 6 | 12813206131799685 |
| 7 | 33758171486592987138461432668177794 |
| 8 | 1435913805026242504952006868879460423767388571975632398910903473535427583 |