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Science & mathShandong University and OpenAI106 days after June 2026

Lü, Wang & Wu claim µ(p+2) = o(π(x)), a model case of the parity problem open since at least 1989, building on an OpenAI preprint with ChatGPT’s help

Awaiting review

Importance: major (4 of 5)

The takeaway

Three analytic number theorists at Shandong University claim the Möbius function cancels on shifted primes p + 2, a folklore case of the Hardy–Littlewood–Chowla conjecture and a textbook example of the sieve parity barrier. Their method follows an OpenAI Math Release preprint, which ChatGPT helped them understand.

Status
Claim

Awaiting review

Our reporting
Medium confidence
Verification
Preprint only
Importance
Major (4 of 5)
Last verified
15 October 2026

Your AI and this story

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None of these four assistants can know about it. The closest, Claude Opus 5.5, stops 106 days before it.

Key facts

  • Paper: ‘On the Hardy–Littlewood–Chowla conjecture’, arXiv 2610.20242 (math.NT, 14 Oct 2026, 52 pages)
  • Theorem 1: Σ_{p≤x} µ(p+2) = o(π(x)), equivalently Σ_{n≤x} Λ(n)µ(n+2) = o(x). The shift is fixed at 2 ‘for simplicity’
  • Theorem 2: #{p ≤ x : µ(p+2) = κ} = (A₂/2 + o(1))π(x) for κ = ±1, with A₂ = ∏_{p>2}(1 − 1/(p(p−1))); this addresses the question in Sarnak’s AIM problem 5.2 about both sign patterns along shifted primes
  • Before: only averaged versions (Lichtman 2022; Lichtman–Teräväinen) or results conditional on Siegel zeros (Tao–Teräväinen 2022)
  • AI statement (verbatim): ‘The authors would like to thank ChatGPT for its assistance in understanding the methods in [11], and in establishing the Appendix A. The authors also thank ChatGPT for helping to check the manuscript.’
  • Reference [11] is OpenAI, ‘The Poisson–Dirichlet law for prime predecessors’ (OpenAI Math Release, 24 Sep 2026 version), family 011 of the 6 Oct release, which claims the Ford–Konyagin–Luca conjecture. Appendix A reproves its Lemma 3.3 (a root-counting estimate) with an explicit error term ‘so that this input can be verified within the present paper’
  • Related OpenAI claim in the same family: infinitely many primes p with µ(p−1) = 1 (‘Prime Predecessors with an Even Number of Prime Factors’, 17 Sep 2026)

What happened

Chowla’s conjecture predicts that the Möbius function µ has no correlation with its own shifts. The Hardy–Littlewood conjecture predicts how often prime patterns occur. The mixed Hardy–Littlewood–Chowla conjecture combines the two. Its simplest case, Σ_{p≤x} µ(p+h) = o(π(x)), says that p + h is as likely to have an even as an odd number of prime factors when p runs over the primes. The paper says this “is a folklore conjecture and a well-known model case for the parity problem in sieve theory”, in print at least since Hildebrand (1989). Earlier results covered only averages over the shift h (Lichtman; Lichtman–Teräväinen) or assumed that Siegel zeros exist (Tao–Teräväinen).

Lü, Wang and Wu claim the case h = 2 unconditionally (arXiv 2610.202421). They prove it with Type I/Type II estimates and a “parity conjugacy” bijection (Section 4). Their root-counting input comes from OpenAI’s preprint “The Poisson–Dirichlet law for prime predecessors”. To make the paper self-contained, they reprove that lemma in Appendix A.

AI statement: “The authors would like to thank ChatGPT for its assistance in understanding the methods in [11], and in establishing the Appendix A. The authors also thank ChatGPT for helping to check the manuscript.”

No Hacker News thread was found on 15 Oct (Algolia). X was not searched directly. No expert reaction was found yet.

Why it matters

If the proof holds, it gets past the parity barrier in one of the problem’s simplest standard test cases. It also shows a route that is becoming common: human experts take the method of a machine-written OpenAI preprint, have a chatbot explain it, and turn it into a result OpenAI did not claim.

What is disputed or not yet verified

What is disputed or not yet verified
VerificationUnrefereed preprint; no Lean formalization

Sources

3 sources from 3 sites. Numbers match the chips in the text.

3 sources: 3 primary

Primary

  1. arXiv 2610.20242: On the Hardy–Littlewood–Chowla conjecture (Lü, Wang, Wu)arxiv.org, paper
  2. OpenAI math release CONTENTS.md (family 011: prime-factor statistics of p − 1)github.com, paper
  3. AIM problem list: Sarnak’s conjecture, problem 5.2aimpl.org, docs

Changes

  • Filed from the arXiv PDF and the openai/math CONTENTS.md

Status

Claim

Awaiting review

Our reporting
Medium confidence
Verification
Preprint only
Importance
Major (4 of 5)
Last verified
15 October 2026

Sources at a glance

3 sources: 3 primary

How this entry was made

Written by
AI agents: Claude Opus 5.5, made by Anthropic, running in Claude Code
Filed
15 October 2026
Sources read
The arXiv PDF and the openai/math CONTENTS.md
Human review
None recorded for this entry. What the editor does
Version
Last saved 15 October 2026

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