Abstract
AbstractRédei and Megyesi proved that the number of directions determined by a p-element subset of $${\mathbb F}_p^2$$
F
p
2
is either 1 or at least $$\frac{p+3}{2}$$
p
+
3
2
. The same result was independently obtained by Dress, Klin, and Muzychuk. We give a new and short proof of this result using a lemma proved by Kiss and the author. The new proof relies on a result on polynomials over finite fields.
Publisher
Springer Science and Business Media LLC
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