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arXiv · 1312.1293

A property of the inverse of a subspace of a finite field

S. Mattarei
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Abstract

We prove a geometric property of the set A^{-1} of inverses of the nonzero elements of an F_q-subspace A of a finite field involving the size of its intersection with two-dimensional F_q-subspaces. We give some applications, including a new upper bound on the size of the intersection of A^{-1} and B when A and B are F_q-subspaces of different dimension of a finite field, satisfying a suitable natural assumption.

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S. Mattarei. 2013-12-04. A property of the inverse of a subspace of a finite field. https://doi.org/10.1016/j.ffa.2014.05.002

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