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 | 3 |
| 2 | 131 |
| 3 | 131 |
| 4 | 343 |
| 5 | 48384 |
| 6 | 578875 |
| 7 | 2686862 |
| 8 | 161656161 |
| 9 | 344363443 |
| 10 | 13666666631 |
| 11 | 22113131122 |
| 12 | 1596916196951 |
| 13 | 3256487846523 |
| 14 | 115345262543511 |
| 15 | 414720808027414 |
| 16 | 15801167176110851 |
| 17 | 39249297679294293 |
| 18 | 988331239932133889 |
| 19 | 988331239932133889 |