Abstract
We prove a trigonometric inequality of Ingham’s type for nonharmonic Fourier series when the gap condition between frequencies does not hold any more.
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Partially supported by grants PB93-1203 of the DGICYT (Spain) and CHRX-CT94-04771 of the UE.
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Jaffard, S., Tucsnak, M. & Zuazua, E. On a theorem of Ingham. The Journal of Fourier Analysis and Applications 3, 577–582 (1997). https://doi.org/10.1007/BF02648885
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DOI: https://doi.org/10.1007/BF02648885