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 A133701 #7 Mar 23 2022 07:39:36 %S A133701 1,1,1,2,0,2,1,1,0,1,2,0,0,0,2,2,2,2,0,0,2,2,0,0,0,0,0,2,1,1,0,1,0,0, %T A133701 0,1,3,0,3,0,0,0,0,0,3,2,2,0,0,2,0,0,0,0,2 %N A133701 A133698 * A051731. %C A133701 Left and right borders = A001227: (1, 1, 2, 1, 2, 2, 2, ...), the number of odd divisors of n. %C A133701 Row sums = A133702, the inverse Mobius transform of A023136. %F A133701 A133698 * A051731 as infinite lower triangular matrices. %e A133701 First few rows of the triangle: %e A133701 1; %e A133701 1, 1; %e A133701 2, 0, 2; %e A133701 1, 1, 0, 1; %e A133701 2, 0, 0, 0, 2; %e A133701 2, 2, 2, 0, 0, 2; %e A133701 2, 0, 0, 0, 0, 0, 2; %e A133701 1, 1, 0, 1, 0, 0, 0, 1; %e A133701 ... %Y A133701 Cf. A051731, A133698, A001227, A133702, A023136. %K A133701 nonn,tabl,more %O A133701 1,4 %A A133701 _Gary W. Adamson_, Sep 21 2007