Best \(L^ p-\)approximation of generalized biaxisymmetric potentials. (English) Zbl 0451.31014
MSC:
31B35 | Connections of harmonic functions with differential equations in higher dimensions |
31A05 | Harmonic, subharmonic, superharmonic functions in two dimensions |
35C15 | Integral representations of solutions to PDEs |
35J05 | Laplace operator, Helmholtz equation (reduced wave equation), Poisson equation |
41A50 | Best approximation, Chebyshev systems |
31B05 | Harmonic, subharmonic, superharmonic functions in higher dimensions |