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Nonquadraticity of Lambert series values and improved bounds for Erdős Problem 1049

For rational bases t=a/b>1t=a/b>1, F(t)=∑n≥1(tn−1)−1F(t)=\sum_{n\ge1}(t^n-1)^{-1} is irrational whenever log⁡b/log⁡a<0.5728\log b/\log a<0.5728, and a formalized refinement reaches 0.5732900.573290. The previous thresholds were 1/2−1/π2≈0.39871/2-1/\pi^2\approx0.3987 (Bundschuh and Väänänen, 1994) and 0.4056830.405683 (W. Cook, September 2026, self-published). Problem 1049 itself stays open: t=3/2t=3/2, with log⁡2/log⁡3≈0.631\log2/\log3\approx0.631, is still outside the region. Along the way, for every integer q≥2q\ge2 the numbers 1,F(q),F(q)21,F(q),F(q)^2 are linearly independent over Q\mathbb Q, so the Erdős-Borwein constant F(2)F(2) is not quadratic irrational. Both follow from one degree criterion for real algebraic bases: no relation of degree at most ee over Q(q)\mathbb Q(q) when eλlog⁡M(q)<log⁡qe\lambda\log M(q)<\log q, with λ=(42963+428220/π2)/202140≈0.42718\lambda=(42963+428220/\pi^2)/202140\approx0.42718.

Exact FrontierDelta

Prior state unknown→proved

Scope and record

Occurred: Oct 7, 2026

Delta type: SOURCE CLAIM

Assumptions: VibeMathed verification: lean-checked. Publication: announcement. AI contribution: ai-discovered. VibeMathed editorial classifications, scores, notes, relations, and dataset structure are CC BY 4.0. Source statements and linked content retain their own rights.

Canonical aliases: Nonquadraticity of Lambert series values and improved bounds for Erdős Problem 1049 · Lambert Nonquadraticity · Problem 1049

Confidence: Not scored

Registry verification: lean checked · announcement · partial

Open the source record ↗

Attribution

VibeMathed
registry · event recorded by

Generative AI
model · ai model contributor · OpenAI

model not named in the source (submitter: GPT-6 Astra via OpenAI Codex)
model · ai model contributor · OpenAI

Costa Lambrinoudis
human · human collaborator

Artifacts and verifiers

Formal Conjectures: Erdős 1049 (open; integer-base variant)

formal registration · pending

Artifact ↗

Compute record

No linked compute attempts recorded.

Lineage and corrections

erdosproblems.com forum thread for Problem 1049 evidence for this event

Nonquadraticity of Lambert series values and improved bounds for Erdős Problem 1049 evidence for this event

Nonquadraticity of Lambert series values and improved bounds for Erdős Problem 1049 parent of this event

This event attributed to Costa Lambrinoudis

Formal Conjectures: Erdős 1049 (open; integer-base variant) evidence for this event

This event attributed to model not named in the source (submitter: GPT-6 Astra via OpenAI Codex)

This event attributed to Generative AI

Erdos Problem 1049 evidence for this event

Twitter Announcement evidence for this event

W. Cook, Geometric Moments and Rational Lambert Values (earlier 0.405683 threshold) evidence for this event

For rational bases t=a/b>1t=a/b>1, F(t)=∑n≥1(tn−1)−1F(t)=\sum_{n\ge1}(t^n-1)^{-1} is irrational whenever log⁡b/log⁡a<0.5728\log b/\log a<0.5728, and a formalized refinement reaches 0.5732900.573290. The previous thresholds were 1/2−1/π2≈0.39871/2-1/\pi^2\approx0.3987 (Bundschuh and Väänänen, 1994) and 0.4056830.405683 (W. Cook, September 2026, self-published). Problem 1049 itself stays open: t=3/2t=3/2, with log⁡2/log⁡3≈0.631\log2/\log3\approx0.631, is still outside the region. Along the way, for every integer q≥2q\ge2 the numbers 1,F(q),F(q)21,F(q),F(q)^2 are linearly independent over Q\mathbb Q, so the Erdős-Borwein constant F(2)F(2) is not quadratic irrational. Both follow from one degree criterion for real algebraic bases: no relation of degree at most ee over Q(q)\mathbb Q(q) when eλlog⁡M(q)<log⁡qe\lambda\log M(q)<\log q, with λ=(42963+428220/π2)/202140≈0.42718\lambda=(42963+428220/\pi^2)/202140\approx0.42718. parent of this event

VibeMathed record: Nonquadraticity of Lambert series values and improved bounds for Erdős Problem 1049 evidence for this event

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