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 A051486 #8 Jun 13 2013 14:31:35 %S A051486 1,1,1,2,1,1,2,2,2,1,1,2,1,2,4,2,1,2,1,1,2,1,0,2,4,3,2,2,2,3,4,2,0,1, %T A051486 2,1,1,2,1,0,0,2,4,2,0,0,3,6,3,0,0,4,8,4,0,0,3,6,3,0,0,2,4,2,0,0,1,2, %U A051486 1,1,2,1,0,0,0,2,4,2,0,0,0,1,2,1,2,4,2,0,0,1,6,9,4,0,0,2,6,6,2 %N A051486 Triangle T(n,k) = number of symmetric Boolean functions of n variables and rank from 0 to 2^n. %H A051486 <a href="/index/Bo#Boolean">Index entries for sequences related to Boolean functions</a> %e A051486 [1, 1], [1, 2, 1], [1, 2, 2, 2, 1], [1, 2, 1, 2, 4, 2, 1, 2, 1], ... %Y A051486 Row sums give A011782. %K A051486 nonn,tabf,nice %O A051486 0,4 %A A051486 _Vladeta Jovovic_