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 | 6 |
| 3 | 91 |
| 4 | 2910 |
| 5 | 187178 |
| 6 | 24019884 |
| 7 | 6154080275 |
| 8 | 3151538898870 |
| 9 | 3227331249742334 |
| 10 | 6609648919647088788 |
| 11 | 27073195436180090799006 |
| 12 | 221783764770326660974008300 |
| 13 | 3633705802215756626623500731892 |
| 14 | 119069276624759801067298501607804376 |