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 A131894 #6 Mar 04 2022 02:05:29 %S A131894 1,6,3,11,6,5,16,9,8,7,21,12,11,10,9,26,15,14,13,12,11,31,18,17,16,15, %T A131894 14,13,36,21,20,19,18,17,16,15,41,24,23,22,21,20,19,18,17,46,27,26,25, %U A131894 24,23,22,21,20,19 %N A131894 A131843 * A000012. %C A131894 Left column = A016861, 5n + 1: (1, 6, 11, 16, 21, 26, ...). %C A131894 Row sums = A131895: (1, 9, 22, 40, 63, ...). %C A131894 Triangle A131896 = A000012 * A131843. %F A131894 Triangle read by rows, partial row sums starting from the right, of A131843. %e A131894 First few rows of the triangle: %e A131894 1; %e A131894 6, 3; %e A131894 11, 6, 5; %e A131894 16, 9, 8, 7; %e A131894 21, 12, 11, 10, 9; %e A131894 26, 15, 14, 13, 12, 11; %e A131894 ... %Y A131894 Cf. A131843, A131895, A131896. %K A131894 nonn,tabl %O A131894 0,2 %A A131894 _Gary W. Adamson_, Jul 24 2007