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 A091745 #4 Sep 26 2012 05:05:36 %S A091745 1,0,-12,240,7056,-1472640,60785472,24634471680,-6666732039936, %T A091745 -266945607045120,818181307311879168,-225753930347735961600, %U A091745 -114700401016766429097984,133755245359458345703342080 %N A091745 Alternating row sums of triangle A060063. %F A091745 a(n)=sum(A060063(n, m)*(-1)^m, m=0..n), n>=0. %K A091745 sign,easy %O A091745 0,3 %A A091745 _Wolfdieter Lang_, Feb 13 2004