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) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 21 |
| 4 | 126 |
| 5 | 504 |
| 6 | 987 |
| 7 | 5922 |
| 8 | 23688 |
| 9 | 2178309 |
| 10 | 13069854 |
| 11 | 52279416 |
| 12 | 10610209857723 |
| 13 | 63661259146338 |
| 14 | 254645036585352 |