Uniform boundedness of some trigonometric polynomials of many variables
The paper deals with uniform boundedness of trigonometric polynomials of several variables \[ \sum_{(n_ 1,...,n_ m)\in A}\frac{\sin n_ 1x_ 1}{n_ 1}...\frac{\sin n_ mx_ m}{n_ m}, \] where the sum is taken over all ``integer'' points of an arbitrary domain \(A\subset (0,\infty)^ m\) which is ``convex with respect to all coordinate directions''.
scientific article; zbMATH DE number 4048321