English

Efficient polynomial time algorithms computing industrial-strength primitive roots

Symbolic Computation 2008-12-09 v2 Number Theory

Abstract

E. Bach, following an idea of T. Itoh, has shown how to build a small set of numbers modulo a prime p such that at least one element of this set is a generator of \pFp\pF{p}\cite{Bach:1997:sppr,Itoh:2001:PPR}. E. Bach suggests also that at least half of his set should be generators. We show here that a slight variant of this set can indeed be made to contain a ratio of primitive roots as close to 1 as necessary. We thus derive several algorithms computing primitive roots correct with very high probability in polynomial time. In particular we present an asymptotically O(1ϵlog1.5(p)+log2(p))O^{\sim}(\sqrt{\frac{1}{\epsilon}}log^1.5(p) + \log^2(p)) algorithm providing primitive roots of pp with probability of correctness greater than 1ϵ1-\epsilon and several O(logα(p))O(log^\alpha(p)), α5.23\alpha \leq 5.23 algorithms computing "Industrial-strength" primitive roots with probabilities e.g. greater than the probability of "hardware malfunctions".

Keywords

Cite

@article{arxiv.cs/0409029,
  title  = {Efficient polynomial time algorithms computing industrial-strength primitive roots},
  author = {Jacques Dubrois and Jean-Guillaume Dumas},
  journal= {arXiv preprint arXiv:cs/0409029},
  year   = {2008}
}