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 | 5 |
| 3 | 57 |
| 4 | 1053 |
| 5 | 27057 |
| 6 | 891765 |
| 7 | 35883369 |
| 8 | 1705399821 |
| 9 | 93486709089 |
| 10 | 5806695485925 |
| 11 | 403035074738073 |
| 12 | 30915209058366717 |
| 13 | 2597006055407919633 |
| 14 | 237114260894842246485 |
| 15 | 23379981536098259658441 |
| 16 | 2475981772053312305191149 |
| 17 | 280285314108547303508788161 |
| 18 | 33774891856931450901116286405 |