English

On the equation $N_{p_1}(E)\cdot N_{p_2}(E)\cdots N_{p_k}(E)=n$

Number Theory 2026-01-22 v2 Algebraic Geometry

Abstract

For a given elliptic curve E/QE/\mathbb{Q}, let Np(E)N_p(E) be the number of points on EE modulo pp for a prime of good reduction for EE. Given integer nn, let Gk(E,n)G_k(E,n) be the number of kk-tuples of p1<p2<<pkp_1<p_2<\ldots <p_k primes of good reduction for EE, for which the equation in the title holds, then on assuming the Generalized Riemann Hypothesis for elliptic curves without CM (and unconditionally if the curves have complex multiplication), I show that limnGk(E,n)=\varlimsup_{n\to\infty} G_k(E,n)=\infty for any integer k3k\geq 3. I conjecture that this result also holds for k=1,2k=1,2 i.e. this conjecture says that there are arbitrarily long ``elliptic progressions of primes'' i.e. sequences of primes p1<p2<<pmp_1<p_2<\cdots <p_m of arbitrary lengths mm such that Np1(E)=Np2(E)==Npm(E)N_{p_1}(E)=N_{p_2}(E)=\cdots =N_{p_m}(E).

Keywords

Cite

@article{arxiv.1711.06283,
  title  = {On the equation $N_{p_1}(E)\cdot N_{p_2}(E)\cdots N_{p_k}(E)=n$},
  author = {Kirti Joshi},
  journal= {arXiv preprint arXiv:1711.06283},
  year   = {2026}
}

Comments

35 Pages. Substantially expanded and completely revised version. To appear in The Ramanujan Journal

R2 v1 2026-06-22T22:48:41.202Z