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 | 5 |
| 2 | 249 |
| 3 | 17395 |
| 4 | 862953 |
| 5 | 53074167 |
| 6 | 3105936858 |
| 7 | 181382499259 |
| 8 | 10750194262698 |
| 9 | 631206895803116 |
| 10 | 37197513508819191 |
| 11 | 2191568660367709311 |
| 12 | 129026759279686110418 |
| 13 | 7600920859497795763717 |
| 14 | 447657086066162084823497 |
| 15 | 26365510156948695071183306 |