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) |
|---|---|
| 4 | 0 |
| 5 | 0 |
| 6 | 2 |
| 7 | 0 |
| 8 | 5 |
| 9 | 0 |
| 10 | 15 |
| 11 | 0 |
| 12 | 44 |
| 13 | 0 |
| 14 | 129 |
| 15 | 0 |
| 16 | 407 |
| 17 | 0 |
| 18 | 1349 |
| 19 | 0 |
| 20 | 4638 |
| 21 | 0 |
| 22 | 16425 |
| 23 | 0 |