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 A155076 #4 May 12 2018 20:19:25 %S A155076 1,-1,1,-1,0,1,-1,-1,0,1,-1,-1,0,0,1,-1,-1,-1,0,0,1,-1,-1,-1,0,0,0,1, %T A155076 -1,-1,-1,-1,0,0,0,1,-1,-1,-1,-1,0,0,0,0,1,-1,-1,-1,-1,-1,0,0,0,0,1, %U A155076 -1,-1,-1,-1,-1,0,0,0,0,0,1,-1,-1,-1,-1,-1,-1,0,0,0,0,0,1,-1,-1,-1,-1,-1,-1,0 %N A155076 Triangle read by rows. The main diagonal is positive. If rowindex >= 2*columnindex then -1 else 0. %C A155076 Matrix inverse of this triangle is A155077. %e A155076 Table begins: %e A155076 1, %e A155076 -1,1, %e A155076 -1,0,1, %e A155076 -1,-1,0,1, %e A155076 -1,-1,0,0,1, %e A155076 -1,-1,-1,0,0,1, %e A155076 -1,-1,-1,0,0,0,1, %e A155076 -1,-1,-1,-1,0,0,0,1, %e A155076 -1,-1,-1,-1,0,0,0,0,1, %Y A155076 Cf. A000123. %K A155076 sign,tabl %O A155076 1,1 %A A155076 _Mats Granvik_, _Gary W. Adamson_, Jan 19 2009