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 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 691 |
| 7 | 2 |
| 8 | 3617 |
| 9 | 43867 |
| 10 | 174611 |
| 11 | 155366 |
| 12 | 236364091 |
| 13 | 1315862 |
| 14 | 6785560294 |
| 15 | 6892673020804 |
| 16 | 7709321041217 |
| 17 | 151628697551 |
| 18 | 26315271553053477373 |
| 19 | 308420411983322 |
| 20 | 261082718496449122051 |
| 21 | 3040195287836141605382 |
| 22 | 5060594468963822588186 |