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 A091760 #2 Mar 30 2012 18:58:54 %S A091760 1,3,9,63,555,6303,87381,1434891,27272727,589486923,14288622513, %T A091760 384034370151,11338782475059,364911575317383,12716046006693165, %U A091760 477070508584969299,19174662804725408175,822058028667720327891 %N A091760 0^n+3((n+2)^n/(n+3)-(-1)^n/(n+3)). %Y A091760 Cf. A083063. %K A091760 easy,nonn %O A091760 0,2 %A A091760 _Paul Barry_, Feb 03 2004