Complete biorthogonal systems of Bessel functions
Journal Title: Математичні Студії - Year 2017, Vol 48, Issue 2
Abstract
Let ν≥−1/2 and (ρk)k∈N be a sequence of nonzero complex numbers such that ρ2k≠ρ2m for k≠m. We prove that if the system {xρk−−−√Jν(xρk):k∈N} of Bessel functions of the first kind of index ν≥−1/2 is exact (i.e. complete and minimal) in the space L2(0;1), then its biorthogonal system is also exact in L2(0;1).
Authors and Affiliations
Bohdan Vynnyts’kyi, Ruslan Khats'
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