A Fourier series in which there are large gaps between nonzero terms or .
Lacunary Fourier Series
See also
Fourier SeriesExplore with Wolfram|Alpha
Cite this as:
Weisstein, Eric W. "Lacunary Fourier Series." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/LacunaryFourierSeries.html