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.
Integer}},{k=1};While[PowerMod[19,k,k]!=n,k++];k]; Array[ clk,55] (* _Harvey P. Dale's wiki page.
Integer}},{k=1};While[PowerMod[19,k,k]!=n,k++];k]; Array[ clk,55] (* _Harvey P. Dale has authored 0 sequences.