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 A127140 #6 Feb 14 2022 21:27:09 %S A127140 1,-4,1,-6,0,1,4,-4,0,1,-10,0,0,0,1,24,-6,-4,0,0,1,-14,0,0,0,0,0,1,0, %T A127140 4,0,-4,0,0,0,1,9,0,-6,0,0,0,0,0,1,40,-10,0,0,-4,0,0,0,0,1 %N A127140 Square of triangle A127139, row sums = A101035. %C A127140 Row sums = A101035: (1, -3, -5, 1, -9, 15, ...). A127140 * [1, 2, 3, ...] = A055615: (1, -2, -3, 0, -5, 6, -7, ...). %F A127140 Square of A127139. %e A127140 First few rows of the triangle: %e A127140 1; %e A127140 -4, 1; %e A127140 -6, 0, 1; %e A127140 4, -4, 0, 1; %e A127140 -10, 0, 0, 0, 1; %e A127140 24, -6, -4, 0, 0, 1; %e A127140 -14, 0, 0, 0, 0, 0, 1; %e A127140 0, 4, 0, -4, 0, 0, 0, 1; %e A127140 9, 0, -6, 0, 0, 0, 0, 0, 1; %e A127140 ... %Y A127140 Cf. A127139, A101035, A055615. %K A127140 tabl,sign %O A127140 1,2 %A A127140 _Gary W. Adamson_, Jan 06 2007