On nonnegative entire solutions of second-order semilinear elliptic systems

We consider the second-order semilinear elliptic system $$ Delta u_i=P_i(x)u_{i+1}^{alpha_i}quadhbox{in }mathbb{R}^N, quad i=1,2,dots,m $$ with nonnegative continuous functions $P_i$. We establish nonexistence criteria of nonnegative nontrivial entire solutions for this system. We also proved a Liouville type theorem for nonnegative entire solutions.