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) |
|---|---|
| 2 | 1 |
| 3 | 5 |
| 4 | 45 |
| 5 | 198 |
| 6 | 4820 |
| 7 | 37923 |
| 8 | 1021300 |
| 9 | 6546092 |
| 10 | 514236897 |
| 11 | 3166978245 |
| 12 | 543912789629 |
| 13 | 26110433895907 |
| 14 | 1064987485213631 |
| 15 | 39225481587293096 |