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 A047128 #4 Mar 30 2012 18:56:53 %S A047128 1,4,15,56,211,798,3030,11550,44193,169652,653158,2521038,9752516, %T A047128 37802636,146792136,570924940,2223730395,8672669484,33864089798, %U A047128 132372227670,517947357111,2028479976186,7950990968079,31189593428478 %N A047128 T(n,n+3), array T as in A047120. %K A047128 nonn %O A047128 0,2 %A A047128 _Clark Kimberling_