-2678domain: ZAppears in sequencesLet 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. (1+2*x) - Sum_{n>=1} c(n)/h(n).at n=63A151684G.f. A(x) satisfies: A(x)^8 = A(x^2)^4 + 8*x.at n=6A223026Write 2*x/(1-x) in the form Sum_{j>=1} ((1-x^j)^a(j) - 1).at n=49A290973