English

A question about points on an elliptic curve with prime denominator

Number Theory 2023-07-19 v1

Abstract

Let E be an elliptic curve defined by a Weierstrass equation with integer coefficients. Any rational point on E other than the identity is of the form (x(P)/z(P)2,y(P)/z(P)3) ( x(P) / z(P)^2 , y(P) / z(P)^3 ) where x(P),y(P)Z x(P), y(P) \in \mathbb Z and z(P)N z(P) \in \mathbb N and in addition both gcd(x(P),z(P))=1 \gcd( x(P) , z(P) ) = 1 and gcd(y(P),z(P))=1 \gcd( y(P) , z(P) ) = 1 hold. The question is: how often is z(P) z(P) a prime number?

Keywords

Cite

@article{arxiv.2307.09406,
  title  = {A question about points on an elliptic curve with prime denominator},
  author = {Simon L Rydin Myerson},
  journal= {arXiv preprint arXiv:2307.09406},
  year   = {2023}
}

Comments

3 pages. This is a slightly edited version of an open question I submitted to the problem session of the JA2023 conference, where it was communicated by Michel Waldschmidt