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 | 0 |
| 2 | 0 |
| 3 | 1 |
| 4 | 16 |
| 5 | 78 |
| 6 | 324 |
| 7 | 1141 |
| 8 | 3885 |
| 9 | 12630 |
| 10 | 40315 |
| 11 | 126604 |
| 12 | 393986 |
| 13 | 1216525 |
| 14 | 3737912 |
| 15 | 11438230 |
| 16 | 34898189 |
| 17 | 106217986 |
| 18 | 322683051 |