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 A047106 #4 Mar 30 2012 18:56:53 %S A047106 1,2,6,21,73,261,957,3547,13267,50027,189780,723456,2769333,10637790, %T A047106 40984228,158306891,612856611,2377260192,9237543329,35951472496, %U A047106 140116098727,546778366195,2136168391753,8354417782742,32705042089703 %N A047106 T(n,n+1), array T as in A047100. %K A047106 nonn %O A047106 0,2 %A A047106 _Clark Kimberling_