SYNTHESIS IN THE KERNEL OF THE THREE-SIDED CONVOLUTION OPERATOR
摘要
One says that an approximation theorem holds for a homogeneous convolution-type equation if any solution of this equation can be approximated by its elementary solutions. In this paper, we state a necessary and sufficient condition for the validity of the approximation theorem for the homogeneous equation of three-way convolution for any choice of a convex domain and its characteristic function.