Waring's problem in quadratic number fields
Let be a quadratic imaginary number field of discriminant . For let denote the order of conductor in and its modular invariant which is known to generate the ring class field modulo over . The coefficients of the minimal equation of being quite large Weber considered in [We] the functions defined below and thereby obtained simpler generators of the ring class fields. Later on the singular values of these functions played a crucial role in Heegner’s solution [He] of the class...