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 | 1 |
| 2 | 9 |
| 3 | 18 |
| 4 | 38 |
| 5 | 98 |
| 6 | 384 |
| 7 | 2580 |
| 8 | 2580 |
| 9 | 2580 |
| 10 | 2580 |
| 11 | 2580 |
| 12 | 367574 |
| 13 | 721449 |
| 14 | 3879720 |
| 15 | 3879720 |
| 16 | 53671968 |
| 17 | 53671968 |
| 18 | 223610114 |