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.
[0]); return scalar(grep { !(hammingweight($'s wiki page.
[0]); return scalar(grep { !(hammingweight($ has authored 0 sequences.