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 | 4 |
| 1 | 12 |
| 2 | 144 |
| 3 | 33024 |
| 4 | 2147549184 |
| 5 | 9223372041149743104 |
| 6 | 170141183460469231750134047789593657344 |
| 7 | 57896044618658097711785492504343953926975274699741220483192166611388333031424 |