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 A130026 #5 Feb 20 2022 01:39:36 %S A130026 1,2,1,3,0,1,4,3,0,1,5,0,0,0,1,6,5,4,0,0,1,7,0,0,0,0,0,1,8,7,0,5,0,0, %T A130026 0,1,9,0,7,0,0,0,0,0,1,10,9,0,0,6,0,0,0,0,1 %N A130026 Triangle (n,k) by columns, arithmetic sequences interspersed with k zeros. %C A130026 Row sums = A081307: (1, 3, 4, 8, 6, 16, 8, 21, 17, ...). %F A130026 Arithmetic sequences by columns, (1,2,3,...); (1,3,5,...); (1,4,7,...); interspersed with k zeros, k=0,1,2,... %e A130026 First few rows of the triangle: %e A130026 1; %e A130026 2, 1; %e A130026 3, 0, 1; %e A130026 4, 3, 0, 1; %e A130026 5, 0, 0, 0, 1; %e A130026 6, 5, 4, 0, 0, 1; %e A130026 7, 0, 0, 0, 0, 0, 1; %e A130026 ... %Y A130026 Cf. A081307, A130027. %K A130026 nonn,tabl %O A130026 0,2 %A A130026 _Gary W. Adamson_, May 02 2007