83109648780domain: NAppears in sequencesExpansion of g.f. A(x) satisfying theta_4(x) = Sum_{n=-oo..+oo} x^n * (2*A(x) - x^n)^(n-1) where theta_4(x) = Sum_{n=-oo..+oo} (-1)^n * x^(n^2) is a Jacobi theta function.at n=13A363574