Uniform irreducibility and Galois groups of generalized Laguerre polynomials

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Version 1 / Nov 04, 2026 / CC BY 4.0

Abstract

We prove that the generalized Laguerre polynomial Hn,sH_{n,s} is irreducible over Q\mathbb Q and has Galois group containing AnA_n for every positive integer ss, once nn exceeds an effective absolute constant. Equivalently, every numerator and denominator in the exponential Pad\'e table has these properties once its own degree is sufficiently large. The exceptional positive integral pairs form an effectively computable finite set. The proof combines integral traces at degenerate fibers, Pad\'e resultants, and an energy inequality for Galois-invariant positive semidefinite forms on the roots.

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Version history

  1. v1Submitted by Khai-Hoan Nguyen-DangInitial depositCurrentNov 04, 2026