Almost prime Pythagorean triples in thin orbits
Number Theory
2010-01-05 v1 Dynamical Systems
Abstract
For the ternary quadratic form Q(x) = x^2 + y^2 - z^2 and a non-zero Pythagorean triple x_0 in Z^3 lying on the cone Q(x) = 0, we consider an orbit O = x_0 Gamma of a finitely generated subgroup Gamma < SO_Q(Z) with critical exponent exceeding 1/2. We find infinitely many Pythagorean triples in O whose hypotenuse, area, and product of side lengths have few prime factors, where "few" is explicitly quantified. We also compute the asymptotic of the number of such Pythagorean triples of norm at most T, up to bounded constants.
Keywords
Cite
@article{arxiv.1001.0370,
title = {Almost prime Pythagorean triples in thin orbits},
author = {Alex Kontorovich and Hee Oh},
journal= {arXiv preprint arXiv:1001.0370},
year = {2010}
}
Comments
37 pages, 8 figures, 1 table