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) |
|---|---|
| 1 | 2 |
| 2 | 12 |
| 3 | 224 |
| 4 | 61440 |
| 5 | 4160749568 |
| 6 | 18158513697557839872 |
| 7 | 337623910929368631717566993311207522304 |
| 8 | 115339776388732929035197660848497720713218148788040405586178452820382218977280 |