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 A128432 #5 Feb 18 2022 22:18:45 %S A128432 1,-1,0,-1,-1,0,0,0,0,0,-1,-1,-1,-1,0,1,0,0,0,1,0,-1,-1,-1,-1,-1,-1,0, %T A128432 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,1,0,0,0,1,0,1,0 %N A128432 Triangle read by rows: A128407 * A054521. %C A128432 Row sums = A023900: (1, -1, -2, 0, -4, 2, -6, ...) Left border = mu(n), A008683. %F A128432 A128407 * A054521 as infinite lower triangular matrices. %e A128432 First few rows of the triangle: %e A128432 1; %e A128432 -1, 0; %e A128432 -1, -1, 0; %e A128432 0, 0, 0, 0; %e A128432 -1, -1, -1, -1, 0; %e A128432 1, 0, 0, 0, 1, 0; %e A128432 -1, -1, -1, -1, -1, -1, 0; %e A128432 0, 0, 0, 0, 0, 0, 0, 0; %e A128432 ... %Y A128432 Cf. A128407, A054521, A008683, A023900. %K A128432 tabl,sign %O A128432 1,1 %A A128432 _Gary W. Adamson_, Mar 03 2007