For lattice polytopes P1; : : : ; Pk ⊆ Rd, Bihan (2016) introduced the discrete mixed volume DMV(P1; : : : ; Pk) in analogy to the classical mixed volume. In this note we study the associated mixed Ehrhart polynomial MEP1;:::;Pk (n) = DMV(nP1; : : : ; nPk). We provide a characterization of all mixed Ehrhart coefficients in terms of the classical multivariate Ehrhart polynomial. Bihan (2016) showed that the discrete mixed volume is always non- negative. Our investigations yield simpler proofs for certain special cases. We also introduce and study the associated mixed h*-vector. We show that for large enough dilates rP1; : : : ; rPk the corresponding mixed h*-polynomial has only real roots and as a consequence the mixed h*-vector becomes non- negative.
