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 | 1 |
| 3 | 3 |
| 4 | 10 |
| 5 | 55 |
| 6 | 2369 |
| 7 | 14026242 |
| 8 | 29284932065996223 |
| 9 | 468863491068204425232922367146585 |
| 10 | 1994324729204021501147398087008429476673379600542622915802043455294332 |