English

Benford's Law for Coefficients of Newforms

Number Theory 2020-04-13 v2

Abstract

Let f(z)=n=1λf(n)e2πinzSknew(Γ0(N))f(z)=\sum_{n=1}^\infty \lambda_f(n)e^{2\pi i n z}\in S_{k}^{new}(\Gamma_0(N)) be a normalized Hecke eigenform of even weight k2k\geq2 on Γ0(N)\Gamma_0(N) without complex multiplication. Let P\mathbb{P} denote the set of all primes. We prove that the sequence {λf(p)}pP\{\lambda_f(p)\}_{p\in\mathbb{P}} does not satisfy Benford's Law in any base b2b\geq2. However, given a base b2b\geq2 and a string of digits SS in base bb, the set Aλf(b,S):={p prime : the first digits of λf(p) in base b are given by S} A_{\lambda_f}(b,S):=\{\text{$p$ prime : the first digits of $\lambda_f(p)$ in base $b$ are given by $S$}\} has logarithmic density equal to logb(1+S1)\log_b(1+S^{-1}). Thus {λf(p)}pP\{\lambda_f(p)\}_{p\in\mathbb{P}} follows Benford's Law with respect to logarithmic density. Both results rely on the now-proven Sato-Tate Conjecture.

Keywords

Cite

@article{arxiv.1407.1577,
  title  = {Benford's Law for Coefficients of Newforms},
  author = {Marie Jameson and Jesse Thorner and Lynnelle Ye},
  journal= {arXiv preprint arXiv:1407.1577},
  year   = {2020}
}

Comments

10 pages. Referee comments implemented. To appear in International Journal of Number Theory