Abstract
The best known asymptotic bit complexity bound for factoring univariate polynomials over finite fields grows with \(d^{1.5 + o (1)}\) for input polynomials of degree d, and with the square of the bit size of the ground field. It relies on a variant of the Cantor–Zassenhaus algorithm which exploits fast modular composition. Using techniques by Kaltofen and Shoup, we prove a refinement of this bound when the finite field has a large extension degree over its prime field. We also present fast practical algorithms for the case when the extension degree is smooth.
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Hoeven, J.v.d., Lecerf, G. Univariate polynomial factorization over finite fields with large extension degree. AAECC 35, 121–149 (2024). https://doi.org/10.1007/s00200-021-00536-1
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DOI: https://doi.org/10.1007/s00200-021-00536-1