2019/12/10 by Mossinghoff, Michael J., Silva, Tomás Oliveira e, Trudgian, Tim
#11M26 #11N60 #11Y35 #FOS: Mathematics #Number Theory (math.NT)
paper · doi:10.48550/arxiv.1912.04972
Let Rk(x) denote the error incurred by approximating the number of k-free integers less than x by x/ζ(k). It is well known that Rk(x)=Ω(x(1)/(2k)), and widely conjectured that Rk(x)=O(x(1)/(2k)+ε). By establishing weak linear independence of some subsets of zeros of the Riemann zeta function, we establish an effective proof of the lower bound, with significantly larger bounds on the constant compared to those obtained in prior work. For example, we show that Rk(x)/x1/2k > 3 infinitely often and that Rk(x)/x1/2k < -3 infinitely often, for k=2, 3, 4, and 5. We also investigate R2(x) and R3(x) in detail and establish that our bounds far exceed the oscillations exhibited by these functions over a long range: for 0