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 | 0 |
| 3 | 1 |
| 4 | 4 |
| 5 | 76 |
| 6 | 4232 |
| 7 | 611528 |
| 8 | 222688092 |
| 9 | 205040866270 |
| 10 | 484396550160186 |
| 11 | 2987729989350536868 |
| 12 | 48933147333828638153224 |
| 13 | 2160018687398735805070288200 |
| 14 | 260218032038985813416099131315377 |
| 15 | 86440094822917159858790627703492969772 |