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.
%I A030263 #12 Feb 15 2015 10:16:02 %S A030263 1,2,57,18544,104208775,12244640803344,36193798266945468968, %T A030263 3160642595226430678271332032,9374102814860736866561050257041372709, %U A030263 1067627008939949742128760399369846160513647927040 %N A030263 Number of nonisomorphic commutative groupoids with 1 idempotent. %H A030263 <a href="/index/Gre#groupoids">Index entries for sequences related to groupoids</a> %K A030263 nonn,nice %O A030263 1,2 %A A030263 _Christian G. Bower_, Feb 15 1998 and May 15 1998