Orthonormal expansions of angular momentum functions. (English) Zbl 0334.42017
MSC:
42A32 | Trigonometric series of special types (positive coefficients, monotonic coefficients, etc.) |
42C05 | Orthogonal functions and polynomials, general theory of nontrigonometric harmonic analysis |
42A70 | Trigonometric moment problems in one variable harmonic analysis |
41A50 | Best approximation, Chebyshev systems |