A337267 A335703(2n).
1, 3, 9, 30, 95, 326, 1195, 4478, 17251, 67326, 266331, 1058146, 4216075, 16808282, 67130923, 268281390, 1072424939
Offset: 0
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.