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 | 5 |
| 3 | 34 |
| 4 | 299 |
| 5 | 3226 |
| 6 | 41202 |
| 7 | 607545 |
| 8 | 10153831 |
| 9 | 189628750 |
| 10 | 3913009178 |
| 11 | 88406043991 |
| 12 | 2170372901534 |
| 13 | 57531498837515 |
| 14 | 1637713270797411 |
| 15 | 49830222530823615 |
| 16 | 1613950394999111903 |
| 17 | 55444724259894089718 |
| 18 | 2013760368429942861810 |
| 19 | 77105255895256112519259 |