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 A134839 #6 Mar 27 2022 18:51:55 %S A134839 1,1,3,1,2,4,1,3,3,7,1,2,3,4,6,1,3,4,6,5,12,1,2,3,4,5,6,8,1,3,3,7,5,9, %T A134839 7,15,1,2,4,4,5,8,7,8,13,1,3,3,6,6,9,7,12,9,18 %N A134839 Triangle, n-th row = first n terms in n-th row of an array formed by A051731 * A126988(transform). %C A134839 Right border = sigma(n), A000203: (1, 3, 4, 7, 6, 12, ...). %C A134839 Row sums = A007437: (1, 4, 7, 14, 16, 31, 29, 50, ...). %F A134839 Given the array formed by A051731 * A126988(transform), the triangle by rows = first n terms of n-th row of the array. %e A134839 First few rows of the array: %e A134839 1, 2, 3, 4, 5, 6, 7, ... %e A134839 1, 3, 3, 6, 5, 9, 7, ... %e A134839 1, 2, 4, 4, 5, 8, 7, ... %e A134839 1, 3, 3, 7, 5, 9, 7, ... %e A134839 1, 2, 3, 4, 6, 6, 7, ... %e A134839 1, 3, 4, 6, 5, 12, 7, ... %e A134839 ... %e A134839 First few rows of the triangle: %e A134839 1; %e A134839 1, 3; %e A134839 1, 2, 4; %e A134839 1, 3, 3, 7; %e A134839 1, 2, 3, 4, 6; %e A134839 1, 3, 4, 6, 5, 12; %e A134839 1, 2, 3, 4, 5, 6, 8; %e A134839 ... %Y A134839 Cf. A126988, A051731, A000203, A007437. %K A134839 nonn,tabl %O A134839 1,3 %A A134839 _Gary W. Adamson_, Nov 12 2007