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) |
|---|---|
| 3 | 1 |
| 4 | 3 |
| 5 | 22 |
| 6 | 255 |
| 7 | 3321 |
| 8 | 52948 |
| 9 | 1064988 |
| 10 | 25071525 |
| 11 | 667694395 |
| 12 | 20114706546 |
| 13 | 678833013618 |
| 14 | 25302305856919 |
| 15 | 1033146095157645 |
| 16 | 45956558123679960 |
| 17 | 2213869047416018296 |
| 18 | 114892917344393371209 |
| 19 | 6396625360877830999983 |