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 A157361 #4 Jun 02 2025 01:24:49 %S A157361 1,1,1,1,0,2,1,1,0,1,1,0,0,0,4,1,1,2,0,0,2,1,0,0,0,0,0,6,1,1,0,1,0,0, %T A157361 0,2,1,0,2,0,0,0,0,0,4,1,1,0,0,4,0,0,0,0,4,1,0,0,0,0,0,0,0,0,0,10,1,1, %U A157361 2,1,0,2,0,0,0,0,0,2 %N A157361 Triangle read by rows, A051731 * (A114810 * 0^(n-k)). %C A157361 Row sums = A055653: (1, 2, 3, 3, 5, 6, 7, 5,...) %F A157361 Triangle read by rows, A051731 * (A114810 * 0^(n-k)); where A051731 = the inverse Mobius transform and (A114810 * 0^(n-k)) = an infinite lower triangular matrix with A114810 as the main diagonal: (1, 1, 2, 1, 4, 2, 6,...) and the rest zeros. %e A157361 First few rows of the triangle = %e A157361 1; %e A157361 1, 1; %e A157361 1, 0, 2; %e A157361 1, 1, 0, 1; %e A157361 1, 0, 0, 0, 4; %e A157361 1, 1, 2, 0, 0, 2; %e A157361 1, 0, 0, 0, 0, 0, 6; %e A157361 1, 1, 0, 1, 0, 0, 0, 2; %e A157361 1, 0, 2, 0, 0, 0, 0, 0, 4; %e A157361 1, 1, 0, 0, 4, 0, 0, 0, 0, 4; %e A157361 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 10; %e A157361 1, 1, 2, 1, 0, 2, 0, 0, 0, 0, 0, 2; %e A157361 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 12; %e A157361 1, 1, 0, 0, 0, 0, 6, 0, 0, 0, 0, 0, 0, 6; %e A157361 ... %Y A157361 Cf. A114810, A055653 %K A157361 nonn,tabl %O A157361 1,6 %A A157361 _Gary W. Adamson_, Feb 28 2009