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arXiv · 1603.06267

An asymptotic formula for integer points on Markoff-Hurwitz varieties

Alex Gamburd·Michael Magee·Ryan Ronan
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Abstract

We establish an asymptotic formula for the number of integer solutions to the Markoff-Hurwitz equation \[ x_{1}^{2}+x_{2}^{2}+\ldots+x_{n}^{2}=ax_{1}x_{2}\ldots x_{n}+k. \] When $n\geq4$ the previous best result is by Baragar (1998) that gives an exponential rate of growth with exponent $\beta$ that is not in general an integer when $n\geq 4$. We give a new interpretation of this exponent of growth in terms of the unique parameter for which there exists a certain conformal measure on projective space.

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Alex Gamburd, Michael Magee, Ryan Ronan. 2016-03-20. An asymptotic formula for integer points on Markoff-Hurwitz varieties. https://arxiv.org/abs/1603.06267

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