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The spectrum of multiplicative functions

Andrew Granville·K. Soundararajan
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Abstract

Let S be a subset of the unit disk, and let F(s) denote the class of completely multiplicative functions f such that f(p) is in S for all primes p. The authors' main concern is which numbers arise as mean-values of functions in F(s). More precisely, let Gamma_N(S) = {1/N sum_{n <= N} f(n): f in F(S)} and Gamma(S) = lim_{N -> infinity} Gamma_N(s). The authors call Gamma(S) the spectrum of the set S, and study its properties.

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Andrew Granville, K. Soundararajan. 1999-09-08. The spectrum of multiplicative functions. https://arxiv.org/abs/math/9909190

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