English

A Hardy-Ramanujan type inequality for shifted primes and sifted sets

Number Theory 2022-07-05 v3

Abstract

We establish an analog of the Hardy-Ramanujan inequality for counting members of sifted sets with a given number of distinct prime factors. In particular, we establish a bound for the number of shifted primes p+a below x with k distinct prime factors, uniformly for all positive integers k.

Keywords

Cite

@article{arxiv.2101.03440,
  title  = {A Hardy-Ramanujan type inequality for shifted primes and sifted sets},
  author = {Kevin Ford},
  journal= {arXiv preprint arXiv:2101.03440},
  year   = {2022}
}

Comments

v3. Added hypothesis x>2|a| to Cor. 1 and 3; changed hypothesis in Theorem 1 so that s is ANY pos. integer dividing all members of S (this is needed for Cor. 1 and Cor. 3). Added remarks explaining that gcd{p+a:p+a in Q(E)} is not always 1 or 2