8927532domain: NAppears in sequencesa(n) = coefficient of x^n in A(x) such that C(x)^2 + S(x)^2 = 1 where: C(x) + i*S(x) = Sum_{n=-oo..+oo} i^n * (2*x)^(n^2) * A(x)^n.at n=18A357787