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 | 1 |
| 4 | 1 |
| 5 | 241 |
| 6 | 1441 |
| 7 | 5041 |
| 8 | 13441 |
| 9 | 393121 |
| 10 | 10946881 |
| 11 | 99902881 |
| 12 | 559025281 |
| 13 | 2335441681 |
| 14 | 182348406241 |
| 15 | 4382526067921 |
| 16 | 48882114328321 |
| 17 | 355837396998721 |
| 18 | 5157802930734721 |
| 19 | 312898934463543361 |
| 20 | 7129755898022511361 |
| 21 | 89524038506304371761 |
| 22 | 773103613914955683361 |