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 A130055 #5 Feb 20 2022 01:41:15 %S A130055 1,0,2,-1,0,3,-1,0,0,4,-3,0,0,0,5,0,-2,0,0,0,6,-5,0,0,0,0,0,7,-2,-2,0, %T A130055 0,0,0,0,8,-3,0,-3,0,0,0,0,0,9,0,-6,0,0,0,0,0,0,0,10 %N A130055 A129691 * A127093. %C A130055 Row sums = d(n), A000005: (1, 2, 2, 3, 2, 4, 2, 4, 3, 4, ...). Left column = A130054: (1, 0, -1, -1, -3, 0, -5, -2, -3, 0, ...). %F A130055 A129691 * A127093 as infinite lower triangular matrices. %e A130055 First few rows of the triangle: %e A130055 1; %e A130055 0, 2; %e A130055 -1, 0, 3; %e A130055 -1, 0, 0, 4; %e A130055 -3, 0, 0, 0, 5; %e A130055 0, -2, 0, 0, 0, 6; %e A130055 -5, 0, 0, 0, 0, 0, 7; %e A130055 ... %Y A130055 Cf. A129691, A127093, A000005, A130054. %K A130055 tabl,sign %O A130055 1,3 %A A130055 _Gary W. Adamson_, May 04 2007