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 | 2 |
| 2 | 12 |
| 3 | 232 |
| 4 | 15792 |
| 5 | 4108192 |
| 6 | 4223439552 |
| 7 | 17316156716672 |
| 8 | 283777228606348032 |
| 9 | 18598759772257600748032 |
| 10 | 4875627680189345535622228992 |
| 11 | 5112485673116229482189477259405312 |
| 12 | 21443339558695300334256395183459423465472 |
| 13 | 359759625310995318218730673236935427042834358272 |