Permanent problem IDPPL 058
Number theory
Schoenberg proved that for every c∈ [0,1] the density of { n∈ ℕ : φ(n)<cn} exists. Let this density be denoted by f(c). Is it true that there are no x such that f'(x) exists and is positive?
Schoenberg proved that for every c∈ [0,1] the density of { n∈ ℕ : φ(n)<cn} exists. Let this density be denoted by f(c). Is it true that there are no x such that f'(x) exists and is positive?
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