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 | 2 |
| 2 | 7 |
| 3 | 42 |
| 4 | 495 |
| 5 | 7436 |
| 6 | 153361 |
| 7 | 3853322 |
| 8 | 116503839 |
| 9 | 4127612326 |
| 10 | 167061660005 |
| 11 | 7671346786170 |
| 12 | 392298901133895 |
| 13 | 22113791358359574 |
| 14 | 1365967717507556804 |
| 15 | 91549507266620360316 |
| 16 | 6624242349107514460269 |
| 17 | 514871138228210665592112 |