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.
}]==1&&Length[Select[Tuples[#],UnsameQ@@#&]]==1&]],{n,0,4}] (* _Gus Wiseman's wiki page.
}]==1&&Length[Select[Tuples[#],UnsameQ@@#&]]==1&]],{n,0,4}] (* _Gus Wiseman has authored 0 sequences.