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 A151676 #6 Jan 04 2021 03:49:54
%S A151676 0,1,-1,0,1,-1,-1,1,0,0,2,-1,-2,0,-2,1,5,1,-1,-3,-7,-1,8,8,6,-3,-18,
%T A151676 -16,0,17,31,21,-19,-51,-47,-3,70,106,48,-71,-170,-156,18,243,318,132,
%U A151676 -253,-564,-455,130,819,1024,341,-952,-1849,-1355,606,2789,3199,727,-3410,-5979,-3932,2678,9408,9926,1281,-12047
%N A151676 Let c(n) = x^(2^n-1)*(1-x^(2^n)), g(n) = 1 + x^(2^n-1) + x^(2^n), h(n) = Product_{i=1..n} g(i); then use g.f. Sum_{n>=1} c(n)/h(n).
%Y A151676 Cf. A151684.
%K A151676 sign
%O A151676 0,11
%A A151676 _N. J. A. Sloane_, May 31 2009