An extremal problem for a class of entire functions of exponential type
نویسنده
چکیده
Let f be an entire function of exponential type whose indicator diagram is contained in the segment [−iσ, iσ], σ > 0. Then the upper density of zeros of f is at most cσ where c ≈ 1.508879 is the positive solution of the equation log( √
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تاریخ انتشار 2008