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 | 4 |
| 2 | 68 |
| 3 | 1732 |
| 4 | 51076 |
| 5 | 1657904 |
| 6 | 57793316 |
| 7 | 2117525792 |
| 8 | 80483121028 |
| 9 | 3147565679824 |
| 10 | 125937573689968 |
| 11 | 5133632426499152 |
| 12 | 212530848994367524 |
| 13 | 8914634034287235856 |
| 14 | 378138515326996979168 |
| 15 | 16196097181014298854032 |