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) |
|---|---|
| 3 | 9 |
| 4 | 16 |
| 5 | 65 |
| 6 | 114 |
| 7 | 457 |
| 8 | 800 |
| 9 | 3201 |
| 10 | 5602 |
| 11 | 22409 |
| 12 | 39216 |
| 13 | 156865 |
| 14 | 274514 |
| 15 | 1098057 |
| 16 | 1921600 |
| 17 | 7686401 |
| 18 | 13451202 |
| 19 | 53804809 |
| 20 | 94158416 |
| 21 | 376633665 |
| 22 | 659108914 |
| 23 | 2636435657 |
| 24 | 4613762400 |
| 25 | 18455049601 |
| 26 | 32296336802 |
| 27 | 129185347209 |
| 28 | 226074357616 |
| 29 | 904297430465 |
| 30 | 1582520503314 |