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) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 2 |
| 5 | 46 |
| 6 | 496 |
| 7 | 3004 |
| 8 | 12872 |
| 9 | 43912 |
| 10 | 130816 |
| 11 | 394384 |
| 12 | 1470944 |
| 13 | 6874336 |
| 14 | 33550336 |
| 15 | 151869376 |
| 16 | 622116992 |
| 17 | 2353246336 |
| 18 | 8589869056 |
| 19 | 31961192704 |
| 20 | 125858012672 |
| 21 | 521796316672 |
| 22 | 2199022206976 |
| 23 | 9122012806144 |
| 24 | 36758056208384 |
| 25 | 144536687773696 |
| 26 | 562949936644096 |