Czechoslovak Mathematical Journal, Vol. 68, No. 4, pp. 1067-1077, 2018


On the Győry-Sárközy-Stewart conjecture in function fields

Igor E. Shparlinski

Received February 28, 2017.   Published online April 20, 2018.

Abstract:  We consider function field analogues of the conjecture of Győry, Sárközy and Stewart (1996) on the greatest prime divisor of the product $(ab+1)(ac+1)(bc+1)$ for distinct positive integers $a$, $b$ and $c$. In particular, we show that, under some natural conditions on rational functions $F,G,H \in{\mathbb C}(X)$, the number of distinct zeros and poles of the shifted products $FH+1$ and $GH+1$ grows linearly with $\deg H$ if $\deg H \ge\max\{\deg F, \deg G\} $. We also obtain a version of this result for rational functions over a finite field.
Keywords:  shifted polynomial product; number of zeros
Classification MSC:  11R09, 11S05, 12E05


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Affiliations:   Igor E. Shparlinski, Department of Pure Mathematics, University of New South Wales, Sydney, NSW 2052, Australia, e-mail: igor.shparlinski@unsw.edu.au


 
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