{ "id": "1711.06283", "version": "v1", "published": "2017-11-16T19:02:18.000Z", "updated": "2017-11-16T19:02:18.000Z", "title": "On the equation $N_{p_1}(E)\\cdot N_{p_2}(E)\\cdots N_{p_k}(E)=n$", "authors": [ "Kirti Joshi" ], "comment": "16 pages", "categories": [ "math.NT", "math.AG" ], "abstract": "For a given elliptic curve $E/\\mathbb{Q}$, set $N_p(E)$ to be the number of points on $E$ modulo $p$ for a prime of good reduction for $E$. Given integer $n$, let $G_k(E,n)$ be the number of $k$-tuples of pairwise distinct primes $p_1,\\ldots,p_k$ of good reduction for $E$, for which 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 $\\varlimsup_{n\\to\\infty} G_k(E,n)=\\infty$ for any integer $k\\geq 3$. I also conjecture that this result also holds for $k=1$ and $k=2$. In particular for $k=1$ this conjecture says that there are \"elliptic progressions of primes\" i.e. sequences of primes $p_1