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) |
|---|---|
| 4 | 30 |
| 5 | 2176 |
| 6 | 54036 |
| 7 | 709956 |
| 8 | 6290051 |
| 9 | 42606671 |
| 10 | 237197942 |
| 11 | 1135834242 |
| 12 | 4823607212 |
| 13 | 18563958502 |
| 14 | 65783057592 |
| 15 | 217240417628 |
| 16 | 674884181813 |
| 17 | 1987124979703 |
| 18 | 5579019610088 |
| 19 | 15010371955248 |
| 20 | 38862554420034 |
| 21 | 97163223921924 |
| 22 | 235290234202584 |
| 23 | 553296290481584 |