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arXiv · 0811.4726

Counting decomposable multivariate polynomials

Joachim von zur Gathen
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Abstract

A polynomial f (multivariate over a field) is decomposable if f = g(h) with g univariate of degree at least 2. We determine the dimension (over an algebraically closed field) of the set of decomposables, and an approximation to their number over a finite field. The relative error in our approximations is exponentially decaying in the input size.

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Joachim von zur Gathen. 2009-07-01. Counting decomposable multivariate polynomials. https://arxiv.org/abs/0811.4726

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