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 A026072 #3 Mar 30 2012 18:56:04 %S A026072 1,3,13,76,427,2427,13871,79729,460473,2670394,15540822,90717305, %T A026072 530946697,3114680815,18308774295,107817336510,635942014275, %U A026072 3756423495198,22217666030882,131563775350068 %N A026072 a(n) = T(2n-1,n), where T is the array defined in A024996. %K A026072 nonn %O A026072 1,2 %A A026072 _Clark Kimberling_