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 A080581 #3 Mar 30 2012 16:49:39 %S A080581 3,7,41,1481,2001161,3741092827721,13288522158502275517773641, %T A080581 169583007779069133432367236428607490469443906412681, %U A080581 27845652802113310312113476847179941923868174497365670633864202252163850208710272402337407041603991561 %N A080581 Ratios of successive terms of A079269. %K A080581 nonn %O A080581 1,1 %A A080581 _N. J. A. Sloane_, Feb 22 2003