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 | 2 |
| 1 | 12 |
| 2 | 240 |
| 3 | 65280 |
| 4 | 4294901760 |
| 5 | 18446744069414584320 |
| 6 | 340282366920938463444927863358058659840 |
| 7 | 115792089237316195423570985008687907852929702298719625575994209400481361428480 |