Notes on lacunary Müntz polynomials
We prove that a Müntz system has Chebyshev polynomials on [0,1] with uniformly bounded coefficients if and only if it is lacunary. A sharp Bernstein-type inequality for lacunary Müntz systems is established as well. As an application we show that a lacunary Müntz system fails to be dense inC(A) in the uniform norm for everyA ⊂ [0,1] with positive outer Lebesgue measure. A bounded Remez-type inequality is conjectured for non-dense Müntz systems on [0,1] which would solve Newman’s problem concerning the density of products of Müntz systems.
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- Notes on lacunary Müntz polynomials
Israel Journal of Mathematics
Volume 76, Issue 1-2 , pp 183-192
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