Let p be a prime and f:Zp→C a complex valued function defined on a cyclic group of order p. Define the Fourier transform of f by the formula:
f^(k)=l=0∑p−1f(l)ei2πkl/p(k∈Zp)
Show that if the combined number of zeros of f and f^ is at least p, then f is identically zero.related:
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