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 A345226 #34 Jun 20 2021 03:08:53 %S A345226 1,1,1,2,1,2,1,2,4,1,2,4,5,2,8,5,2,8,5,2,7,16,5,2,7,16,17,2,7,30,17,2, %T A345226 7,30,17,23,7,54,17,23,7,54,51,23,7,95,51,23,7,95,51,23,7,55,161,51, %U A345226 23,7,55,161,139,23,7,55,266,139,23,7,55,266,139,160,7,55,431,139,160,7,55 %N A345226 Irregular triangle, row sums equal A000041; in the format of A233932. %C A345226 The format of A233932 has a Gray code property of one term change in the next row. Using the production matrix shown below, we can obtain an array with row sums of any target sequence. %F A345226 Let P equal the infinite lower triangular matrix with 1's in every row: [(1), (1, 1), (1, 1, 1), ...]. Begin with the following matrix format such that M[n, A001511(k)] = 1, otherwise 0: %F A345226 1 %F A345226 0, 1 %F A345226 1 %F A345226 0, 0, 1 %F A345226 1 %F A345226 0, 1 %F A345226 1 %F A345226 0, 0, 0, 1 %F A345226 ... %F A345226 Replace the 1's with A187219 (the first difference row of A000041), getting M: %F A345226 1 %F A345226 0, 1 %F A345226 1 %F A345226 0, 0, 2 %F A345226 2 %F A345226 0, 4 %F A345226 4 %F A345226 0, 0, 0, 7 %F A345226 ... %F A345226 Perform the operation P * M, getting A345226 as an irregular matrix. The operation P * M is equivalent to taking partial sums of column terms from top to bottom. %e A345226 The first few rows of the array equal A000041 with offset 1 as to sums: %e A345226 1; %e A345226 1, 1; %e A345226 2, 1; %e A345226 2, 1, 2; %e A345226 4, 1, 2; %e A345226 4, 5, 2; %e A345226 8, 5, 2; %e A345226 8, 5, 2, 7; %e A345226 16, 5, 2, 7; %e A345226 16, 17, 2, 7; %e A345226 30, 17, 2, 7; %e A345226 30, 17, 23, 7; %e A345226 54, 17, 23, 7; %e A345226 54, 51, 23, 7; %e A345226 95, 51, 23, 7; %e A345226 95, 51, 23, 7, 55; %e A345226 161, 51, 23, 7, 55; %e A345226 161, 139, 23, 7, 55; %e A345226 ... %e A345226 The leftmost column is (1, 1, 2, 2, 4, 4, 8, 8, ...), being the partial sums of the first column in matrix M: (1, 0, 1, 0, 2, 0, 4, ...). %Y A345226 Cf. A000041, A001511, A070939, A079559, A135764, A187219, A233932. %K A345226 nonn,tabf %O A345226 1,4 %A A345226 _Gary W. Adamson_, Jun 12 2021