ON THE SIMULTANEOUS SIGN CHANGES OF HECKE EIGENVALUES OVER AN INTEGRAL BINARY QUADRATIC FORM.

We consider the simultaneous sign changes of normalized Fourier coefficients associated to two distinct Hecke eigenforms supported at positive integers represented by a primitive integral binary quadratic form with negative discriminant whose class number is 1. We provide a quantitative result for the number of sign changes of such sequence in the interval (x , 2 x ] for sufficiently large x . [ABSTRACT FROM AUTHOR]