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 A030260 #12 Feb 15 2015 10:15:46 %S A030260 1,0,1,38,13872,83360520,10203847031340,31023254154131753920, %T A030260 2765562268014305034000397632,8332535835277886736134596954072281240, %U A030260 960864308045670310058158724983067048253497223280 %N A030260 Number of nonisomorphic commutative groupoids with no idempotents. %H A030260 <a href="/index/Gre#groupoids">Index entries for sequences related to groupoids</a> %Y A030260 Cf. A001329, A001425, A038021. %K A030260 nonn %O A030260 0,4 %A A030260 _Christian G. Bower_, Feb 15 1998 and May 15 1998