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 A158951 #5 Jun 02 2025 01:28:23 %S A158951 1,2,1,3,0,1,4,2,0,1,4,0,1,0,1,7,2,1,1,0,1,5,0,1,0,1,0,1,8,3,0,2,0,1, %T A158951 0,18,0,2,0,1,0,1,0,1,10,2,1,1,1,1,0,1,0,1 %N A158951 Triangle read by rows, A051731 * A158948. %C A158951 Row sums = sigma(n), A000203. Left column = A079247 %F A158951 Triangle read by rows, A051731 * A158948 %e A158951 First few rows of the triangle = %e A158951 1; %e A158951 2, 1; %e A158951 3, 0, 1; %e A158951 4, 2, 0, 1; %e A158951 4, 0, 1, 0, 1; %e A158951 7, 2, 1, 1, 0, 1; %e A158951 5, 0, 1, 0, 1, 0, 1; %e A158951 8, 3, 0, 2, 0, 1, 0, 1; %e A158951 8, 0, 2, 0, 1, 0, 1, 0, 1; %e A158951 10, 2, 1, 1, 1, 1, 0, 1, 0, 1; %e A158951 7, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1; %e A158951 15, 4, 1, 3, 0, 2, 0, 10, 1, 0, 1; %e A158951 8, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1; %e A158951 13, 2, 1, 1, 1, 1, 1, 1, 0, 1, 0, 1, 0, 1; %e A158951 ... %Y A158951 Cf. A158948, A000203, A051731 %K A158951 nonn,tabl %O A158951 1,2 %A A158951 _Gary W. Adamson_ & _Mats Granvik_, Mar 31 2009