ZEROS OF A CROSS-PRODUCT OF THE COULOMB WAVE AND TRICOMI HYPERGEOMETRIC FUNCTIONS.

Motivated by a problem on conditions for the existence of clines in genetics, we show that the positive zeros of a cross-product of the regular Coulomb wave function and the Tricomi hypergeometric function are increasing with respect to one of the parameters. In particular, this implies that the eigenvalues of a certain boundary value problem are increasing with the dimension. [ABSTRACT FROM AUTHOR]