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 A166240 #3 Mar 30 2012 17:25:35 %S A166240 1,1,1,1,1,1,1,2,1,1,1,2,2,1,1,1,3,2,2,1,1,1,3,4,2,2,1,1,1,4,4,4,2,2, %T A166240 1,1,1,1,4,6,4,4,2,2,1,1,1,5,6,7,4,4,2,2,1,1,1,5,9,7,7,4,4,2,2,1,1,1, %U A166240 6,9,11,7,7,4,4,2,2,1,1 %N A166240 Triangle read by rows, A000012 * A152140 as infinite lower triangular matrices. %C A166240 Row sums = A036469, (partial sums of A000009). %C A166240 The triangle = partial sums of A152140 starting from the top down, by columns. %F A166240 Triangle read by rows, A000012 * A152140, where A000012 = an infinite lower triangular matrix with all 1's: [1; 1,1; 1,1,1;...]. %e A166240 First few rows of the triangle = %e A166240 1; %e A166240 1, 1; %e A166240 1, 1, 1; %e A166240 1, 2, 1, 1; %e A166240 1, 2, 2, 1, 1; %e A166240 1, 3, 2, 2, 1, 1; %e A166240 1, 3, 4, 2, 2, 1, 1; %e A166240 1, 4, 4, 4, 2, 2, 1, 1; %e A166240 1, 4, 6, 4, 4, 2, 2, 1, 1; %e A166240 1, 5, 6, 7, 4, 4, 2, 2, 1, 1; %e A166240 1, 5, 9, 7, 7, 4, 4, 2, 2, 1, 1; %e A166240 1, 6, 9, 11, 7, 7, 4, 4, 2, 2, 1, 1; %e A166240 1, 6, 12, 11, 12, 7, 7, 4, 4, 2, 2, 1, 1; %e A166240 1, 7, 12, 16, 12, 12, 7, 7, 4, 4, 2, 2, 1, 1; %e A166240 1, 7, 16, 16, 18, 12, 12, 7, 7, 4, 4, 2, 2, 1, 1; %e A166240 1, 8, 16, 23, 18, 19, 12, 19, 7, 7, 4, 4, 2, 2, 1, 1; %e A166240 ... %Y A166240 A152140, A036469, A000009 %K A166240 nonn,tabl %O A166240 1,8 %A A166240 _Gary W. Adamson_, Oct 09 2009