A Rigorous Proof of a Ramanujan Machine Identity for $-π/4$ via Exact Recurrence Solving

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Authors: Chao Wang
Cited by: 0

Abstract

We prove a polynomial continued fraction identity for the constant $-π/4$, conjectured by the Ramanujan Machine project. The proof proceeds by explicitly solving the underlying second-order linear difference equation. We derive a closed-form expression for the denominator sequence, $q_n = (-1)^n (2n-3)!!\,(n^2+n-1)$, and establish absolute convergence via a Wronskian telescoping argument. The limiting value is reduced by Abel summation to a Beta-function integral, which is evaluated in closed form through an elementary substitution and a single integration by parts, yielding the exact value $-π/4$.

Fields of Study & Subjects

Advanced Mathematical Identities Mathematical functions and polynomials Analytic Number Theory Research

Publication details

Journal / source
arXiv (Cornell University)
Publication date
13 January 2026
Document type
Preprint