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 A026893 #4 Mar 30 2012 18:56:11 %S A026893 1,15,144,1137,8070,53678,342224,2119359,12856752,76826324,453947206, %T A026893 2659486160,15479103062,89636939038,517014933254,2972784038825, %U A026893 17051188983758,97611767361074,557935896092592,3185250335024206 %N A026893 T(2n,n-3), T given by A026780. %K A026893 nonn %O A026893 3,2 %A A026893 _Clark Kimberling_