English

Primitive prime divisors in zero orbits of polynomials

Number Theory 2011-06-06 v2 Dynamical Systems

Abstract

Let (bn)=(b1,b2,...)(b_n) = (b_1, b_2, ...) be a sequence of integers. A primitive prime divisor of a term bkb_k is a prime which divides bkb_k but does not divide any of the previous terms of the sequence. A zero orbit of a polynomial f(z)f(z) is a sequence of integers (cn)(c_n) where the nn-th term is the nn-th iterate of ff at 0. We consider primitive prime divisors of zero orbits of polynomials. In this note, we show that for integers cc and dd, where d>1d > 1 and c±1c \neq \pm 1, every iterate in the zero orbit of f(z)=zd+cf(z) = z^d + c contains a primitive prime whenever zero has an infinite orbit. If c=±1c = \pm 1, then every iterate after the first contains a primitive prime.

Keywords

Cite

@article{arxiv.1009.3971,
  title  = {Primitive prime divisors in zero orbits of polynomials},
  author = {Kevin Doerksen and Anna Haensch},
  journal= {arXiv preprint arXiv:1009.3971},
  year   = {2011}
}

Comments

6 pages

R2 v1 2026-06-21T16:16:35.534Z