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 A152904 #15 Apr 02 2019 05:42:25 %S A152904 1,-1,1,-1,-1,1,0,-1,-1,1,-1,0,-1,-1,1,1,-1,0,-1,-1,1,-1,1,-1,0,-1,-1, %T A152904 1,0,-1,1,-1,0,-1,-1,1,0,0,-1,1,-1,0,-1,-1,1,1,0,0,-1,1,-1,0,-1,-1,1, %U A152904 -1,1,0,0,-1,1,-1,0,-1,-1,1 %N A152904 Triangle read by rows: T(n,k) = A008683(n-k+1); 1<=k<=n; mu(n) "decrescendo". %H A152904 E. Deutsch, L. Ferrari and S. Rinaldi, <a href="https://doi.org/10.1016/j.aam.2004.05.002">Production Matrices</a>, Advances in Applied Mathematics, 34 (2005) pp. 101-122. %F A152904 Triangle read by rows, T(n,k) = A008683(n-k+1) = A008683 in every column = A008683 "decrescendo"d by rows. %e A152904 Triangle begins %e A152904 1; %e A152904 -1, 1; %e A152904 -1, -1, 1; %e A152904 0, -1, -1, 1; %e A152904 -1, 0, -1, -1, 1; %e A152904 1, -1, 0, -1, -1, 1; %e A152904 -1, 1, -1, 0, -1, -1, 1; %e A152904 0, -1, 1, -1, 0, -1, -1, 1; %e A152904 0, 0, -1, 1, -1, 0, -1, -1, 1; %e A152904 ... %e A152904 Production matrix begins %e A152904 -1, 1, %e A152904 -2, 0, 1, %e A152904 -3, 0, 0, 1, %e A152904 -6, 0, 0, 0, 1, %e A152904 -9, 0, 0, 0, 0, 1, %e A152904 -17, 0, 0, 0, 0, 0, 1, %e A152904 -28, 0, 0, 0, 0, 0, 0, 1, %e A152904 -50, 0, 0, 0, 0, 0, 0, 0, 1, %e A152904 -83, 0, 0, 0, 0, 0, 0, 0, 0, 1, %e A152904 -147, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1 ... %e A152904 where first column is -A073776(n+1). - _Paul Barry_, Feb 10 2011 %Y A152904 Cf. A008683, A002321, A073776, A152901, A152902. %Y A152904 Row sums = A002321, the Mertens function. A185694 is an eigensequence. %K A152904 tabl,sign %O A152904 1,1 %A A152904 _Gary W. Adamson_, Dec 14 2008