\documentclass[11pt]{article} \usepackage[a4paper,margin=28mm]{geometry} \usepackage[T1]{fontenc} \usepackage{lmodern} \usepackage{amsmath,amssymb,amsthm,mathtools} \usepackage{microtype,booktabs,array} \usepackage{xcolor} \usepackage[colorlinks=true,linkcolor=blue!45!black,citecolor=blue!45!black,urlcolor=blue!45!black]{hyperref} \hypersetup{pdftitle={Linear independence of even Dirichlet beta values}, pdfauthor={},pdfsubject={Working mathematical draft; independently cross-checked by another model}, pdfcreator={LaTeX}} \setlength{\emergencystretch}{1em} \newtheorem{theorem}{Theorem}[section] \newtheorem{proposition}[theorem]{Proposition} \newtheorem{lemma}[theorem]{Lemma} \newtheorem{corollary}[theorem]{Corollary} \theoremstyle{remark} \newtheorem{remark}[theorem]{Remark} \numberwithin{equation}{section} \DeclareMathOperator{\Span}{span} \DeclareMathOperator{\lcm}{lcm} \DeclareMathOperator{\ord}{ord} \DeclareMathOperator{\Res}{Res} \newcommand{\Q}{\mathbb Q} \newcommand{\Z}{\mathbb Z} \newcommand{\C}{\mathbb C} \newcommand{\N}{\mathbb N} \newcommand{\ii}{\mathrm i} \newcommand{\dd}{\,\mathrm d} \newcommand{\Ht}{\mathsf H} \newcommand{\Dt}{\mathcal D} \newcommand{\matA}{\mathcal A} \newcommand{\Ocal}{\mathcal O} \title{Linear independence of even Dirichlet beta values} \author{\normalsize Research note prepared with Codex} \date{\small Working draft\\2 November 2026} \begin{document} \maketitle \begin{abstract} Let $\beta(s)=1-3^{-s}+5^{-s}-\cdots$ denote the Dirichlet beta function. For all sufficiently large even integers $s$, we prove \[ \dim_{\Q}\Span_{\Q}\{\beta(2),\beta(4),\ldots,\beta(s)\} \geq 0.21\sqrt{\frac{s}{\log s}}. \] \end{abstract} \input{sections/introduction} \input{sections/inputs} \input{sections/forms} \input{sections/arithmetic} \input{sections/estimates} \input{sections/rank} \input{sections/conclusion} \input{references} \end{document}