Primitive sets and an Euler phi function for subsets of {1,2,...,n}

Melvyn B. Nathanson

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arXiv · math/0608150

Primitive sets and an Euler phi function for subsets of {1,2,...,n}

Melvyn B. Nathanson

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Abstract

A nonempty subset A of {1,2,...,n} is called primitive if gcd(A)=1. Let f(n) and f_k(n) denote, respectively, the number of primitive subsets and the number of primitive subsets of cardinality k of {1,2,...,n}. Recursion formulas and asymptotic estimates are obtained for both functions.

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BibTeX RIS

Melvyn B. Nathanson. 2007-09-16. Primitive sets and an Euler phi function for subsets of {1,2,...,n}. https://arxiv.org/abs/math/0608150

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