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 | 0 |
| 1 | 0 |
| 2 | 1 |
| 3 | 6 |
| 4 | 85 |
| 5 | 1370 |
| 6 | 30481 |
| 7 | 778610 |
| 8 | 24409645 |
| 9 | 881325366 |
| 10 | 36635553601 |
| 11 | 1713454403210 |
| 12 | 89415912126223 |
| 13 | 5143372266050837 |
| 14 | 323667807885619744 |
| 15 | 22112062644980805684 |